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Sample records for gouldsboro granite coastal

  1. Strontium isotopes as tracers of water-rocks interactions, mixing processes and residence time indicator of groundwater within the granite-carbonate coastal aquifer of Bonifacio (Corsica, France).

    Science.gov (United States)

    Santoni, S; Huneau, F; Garel, E; Aquilina, L; Vergnaud-Ayraud, V; Labasque, T; Celle-Jeanton, H

    2016-12-15

    This study aims at identifying the water-rock interactions and mixing rates within a complex granite-carbonate coastal aquifer under high touristic pressure. Investigations have been carried out within the coastal aquifer of Bonifacio (southern Corsica, France) mainly composed of continental granitic weathering products and marine calcarenite sediments filling a granitic depression. A multi-tracer approach combining physico-chemical parameters, major ions, selected trace elements, stable isotopes of the water molecule and 87 Sr/ 86 Sr ratios measurements is undertaken for 20 groundwater samples during the low water period in November 2014. 5 rock samples of the sedimentary deposits and surrounding granites are also analysed. First, the water-rock interactions processes governing the groundwater mineralization are described in order to fix the hydrogeochemical background. Secondly, the flow conditions are refined through the quantification of inter aquifer levels mixing, and thirdly, the kinetics of water-rock interaction based on groundwater residence time from a previous study using CFCs and SF 6 are quantified for the two main flow lines. A regional contrast in the groundwater recharge altitude allowed the oxygene-18 to be useful combined with the 87 Sr/ 86 Sr ratios to differentiate the groundwater origins and to compute the mixing rates, revealing the real extension of the watershed and the availability of the resource. The results also highlight a very good correlation between the groundwater residence time and the spatial evolution of 87 Sr/ 86 Sr ratios, allowing water-rock interaction kinetics to be defined empirically for the two main flow lines through the calcarenites. These results demonstrate the efficiency of strontium isotopes as tracers of water-rock interaction kinetics and by extension their relevance as a proxy of groundwater residence time, fundamental parameter documenting the long term sustainability of the hydrosystem. Copyright © 2016

  2. Uranium in granites

    International Nuclear Information System (INIS)

    Maurice, Y.T.

    1982-01-01

    Recent research activities of the Canadian Uranium in Granites Study are presented in 18 papers and 3 abstracts. 'Granites' is used as a generic term for granitoids, granitic rocks, and plutonic rocks

  3. 2005 dossier: granite; Dossier 2005: granite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This document makes a status of the researches carried out by the French national agency of radioactive wastes (ANDRA) about the geologic disposal of high-level and long-lived radioactive wastes in granite formations. Content: 1 - advantage of granitic formations for the geologic disposal; 2 - containers; 3 - design study of a disposal facility in granitic environment; 4 - understanding and modelling of granite; 5 - description of disposal concepts in granitic environment; 6 - long-term and safety aspects; 7 - conclusion. (J.S.)

  4. 2005 dossier: granite

    International Nuclear Information System (INIS)

    2005-01-01

    This document makes a status of the researches carried out by the French national agency of radioactive wastes (ANDRA) about the geologic disposal of high-level and long-lived radioactive wastes in granite formations. Content: 1 - advantage of granitic formations for the geologic disposal; 2 - containers; 3 - design study of a disposal facility in granitic environment; 4 - understanding and modelling of granite; 5 - description of disposal concepts in granitic environment; 6 - long-term and safety aspects; 7 - conclusion. (J.S.)

  5. The GRANIT spectrometer; Le spectrometre GRANIT

    Energy Technology Data Exchange (ETDEWEB)

    Baessler, St. [University of Virginia, Charlottesville, VA 22904 (United States); Oak Ridge Nat. Lab., Oak Ridge, TN 37831 (United States); Beau, M.; Kreuz, M.; Nesvizhevsky, V.V. [ILL, 6 rue Jules Horowitz, Grenoble, F-3804(France); Kurlov, V.N. [ISSP, 2 Institutskaia, Chernogolovka, RU-142432 (Russian Federation); Pignol, G.; Protasov, K.V.; Vezzu, F. [LPSC/IN2P3-UJF-INPG, 53 rue des Martyrs, Grenoble, F-38026 (France); Voronin, A.Y. [Lebedev Institute, 53 Leninskii pr., Moscow, RU-119991 (Russian Federation)

    2010-10-15

    The existence of quantum states of matter in a gravitational field was demonstrated recently in the Institut Laue-Langevin (ILL), Grenoble, in a series of experiments with ultra cold neutrons (UCN). UCN in low quantum states is an excellent probe for fundamental physics, in particular for constraining extra short-range forces; as well as a tool in quantum optics and surface physics. The GRANIT is a follow-up project based on a second-generation spectrometer with ultra-high energy resolution, permanently installed in ILL. It will become operational in 2011. The spectrometer consists of several neutron-optics elements and UCN detectors installed on a massive granite table in an aluminium vacuum chamber with a volume of about 1.5 m{sup 3}. 3 types of detectors will be used at the first stage of the GRANIT experiment: {sup 3}He gaseous proportional counters with extremely low background, position-sensitive nuclear-track UCN detectors will be used to study the spatial distribution in quantum states, and real-time position-sensitive detectors with a resolution of a few hundred microns to measure velocity distributions of neutrons in quantum states. The key elements of the GRANIT spectrometer is a set of mirrors to shape/analyze neutron spectra and to store neutrons in quantum states

  6. Mesozoic Granitic Magmatism in Macao, Southeast China

    Science.gov (United States)

    Quelhas, P. M.; Mata, J.; Lou, U. T.; Ribeiro, M. L.; Dias, Á. A.

    2016-12-01

    Macao ( 30 Km2) is a territory characterized by small granitic intrusions, located along the coastal region of Southeast China (Cathaysia Block). Granitoids occur as different facies, including microgranite dykes, with distinct textural, mineralogical and geochemical features, for which a middle-upper Jurassic age ( 164 Ma) has been proposed. New data suggest that these granitoids are mostly high-K calc-alkaline metaluminous (A/CNK = 0.8 - 1.1) biotite granites, consistent with total absence of primary muscovite. They show variable amounts of SiO2 (67-77%), reflecting different degrees of magmatic evolution. There is also variability in terms of trace elements, particularly Rare Earth Elements (REEs), evidenced by decreasing (La/Sm)N, (Gd/Lu)N, (Ce/Yb)N and (Eu/Eu*)N towards the more evolved samples, which can be partly attributed to fractional crystallization processes. Most of the granitoids are characterized by (La/Yb)N = 3 - 10.8, showing negative Ba, Nb, Sr, Zr, P, Ti and Eu anomalies. On the other hand, microgranite dykes, along with a few more evolved granites, show an opposite tendency, being usually enriched in HREEs relatively to LREEs with (La/Yb)N = 0.4 - 1.1. Our data suggests intermediate genetic affinities between I-type and A-type granites. Although these granitoids are mostly metaluminous (characteristic of I-types), Ga/Al ratios, usually used to identify A-types, are close to the accepted boundary between A-type and other granite types. The affinities with A-type granites are more marked for the more evolved facies, which depict higher values of FeOt/MgO (14 - 60) and K2O/MgO (60 - 250). Their trace element characteristics are also transitional between WPG (Within-plate granites) and Syn-COLG (Collision Granites). We interpret those transitional characteristics (A/I and WPG/Syn-COLG) of Macao granitoids as reflecting an origin by melting of infracrustal sources over a period of high heat transfer from mantle to crust during an extensional tectonic

  7. Granit, Prof. Ragnar Arthur

    Indian Academy of Sciences (India)

    Home; Fellowship. Fellow Profile. Elected: 1964 Honorary. Granit, Prof. Ragnar Arthur Nobel Laureate (Medicine) - 1967. Date of birth: 30 October 1900. Date of death: 11 March 1991. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. Theory Of Evolution. Posted on 23 January 2018. Joint Statement by the ...

  8. Yeguang granite and uranium metallogeny

    International Nuclear Information System (INIS)

    Gong Wenshu

    1988-03-01

    The geological, petrologic and geochemical characteristics of rock body of yeguang granite are discussed with emphasis on clarification of occurrence of uranium in rock body and uranium deposit characteristics related to rock body, based on extensive field observations and laboratory test. View points are presented that granite refers to genetic series of terrestial crust transformation tye and uranium deposit is hot water deposit

  9. Climax granite test results

    Energy Technology Data Exchange (ETDEWEB)

    Ramspott, L.D.

    1980-01-15

    The Lawrence Livermore Laboratory (LLL), as part of the Nevada Nuclear Waste Storage Investigations (NNWSI) program, is carrying out in situ rock mechanics testing in the Climax granitic stock at the Nevada Test Site (NTS). This summary addresses only those field data taken to date that address thermomechanical modeling for a hard-rock repository. The results to be discussed include thermal measurements in a heater test that was conducted from October 1977 through July 1978, and stress and displacement measurements made during and after excavation of the canister storage drift for the Spent Fuel Test (SFT) in the Climax granite. Associated laboratory and field measurements are summarized. The rock temperature for a given applied heat load at a point in time and space can be adequately modeled with simple analytic calculations involving superposition and integration of numerous point source solutions. The input, for locations beyond about a meter from the source, can be a constant thermal conductivity and diffusivity. The value of thermal conductivity required to match the field data is as much as 25% different from laboratory-measured values. Therefore, unless we come to understand the mechanisms for this difference, a simple in situ test will be required to obtain a value for final repository design. Some sensitivity calculations have shown that the temperature field is about ten times more sensitive to conductivity than to diffusivity under the test conditions. The orthogonal array was designed to detect anisotropy. After considering all error sources, anisotropic efforts in the thermal field were less than 5 to 10%.

  10. Uranium enriched granites in Sweden

    International Nuclear Information System (INIS)

    Wilson, M.R.; Aakerblom, G.

    1980-01-01

    Granites with uranium contents higher than normal occur in a variety of geological settings in the Swedish Precambrian, and represent a variety of granite types and ages. They may have been generated by (1) the anatexis of continental crust (2) processes occurring at a much greater depth. They commonly show enrichement in F, Sn, W and/or Mo. Only in one case is an important uranium mineralization thought to be directly related to a uranium-enriched granite, while the majority of epigenetic uranium mineralizations with economic potential are related to hydrothermal processes in areas where the bedrock is regionally uranium-enhanced. (Authors)

  11. Granites and granitoids of the southern region - Granite molybdenite system

    International Nuclear Information System (INIS)

    Issler, R.S.

    1987-01-01

    Economic concentrations of molybdenum are genetically closely associated with acidic and moderately acid granitoids-granites, granodiorites, monzonites and diorites, and are located in two geotectonic settings: subduction-related and rift-related. The aim of this paper is twofold, first succinctly approach the geology, tectonic setting and chemical parameters of the 'granite molybdenite system' as defined by Mutschler and/or alcali granite porphyry bodies emplaced in the North American continent for occasion of a Mesozoic-Fanerozoic extensile event; second to relate the computer-assisted evaluation of 422 major element chemical analysis of granites and granitoids of southern region of Brazil, using chemical fingerprints (SiO 2 ≥ 74. Owt%, Na 2 O ≤ 3.6wt%, K 2 O ≥ 4.5wt%), and K 2 O/Na 2 O ratio > 1.5 developed and testified from North American and Finnish occurrences, may locate molybdenite-bearing granite bodies with high exploration potential. These techniques suggest that some late Precambrian to early Paleozoic granite-rhyolite assemblages inserted at domains of the SG. 22/23 Curitiba/Iguape, SH. 21/22 Uruguaiana/Porto Alegre and SI.22 Lagoa Mirim Sheets, have exploration potential for molybdenum. (author) [pt

  12. Uranium deposits in granitic rocks

    International Nuclear Information System (INIS)

    Nishimori, R.K.; Ragland, P.C.; Rogers, J.J.W.; Greenberg, J.K.

    1977-01-01

    This report is a review of published data bearing on the geology and origin of uranium deposits in granitic, pegmatitic and migmatitic rocks with the aim of assisting in the development of predictive criteria for the search for similar deposits in the U.S. Efforts were concentrated on the so-called ''porphyry'' uranium deposits. Two types of uranium deposits are primarily considered: deposits in pegmatites and alaskites in gneiss terrains, and disseminations of uranium in high-level granites. In Chapter 1 of this report, the general data on the distribution of uranium in igneous and metamorphic rocks are reviewed. Chapter 2 contains some comments on the classification of uranium deposits associated with igneous rocks and a summary of the main features of the geology of uranium deposits in granites. General concepts of the behavior of uranium in granites during crustal evolution are reviewed in Chapter 3. Also included is a discussion of the relationship of uranium mineralization in granites to the general evolution of mobile belts, plus the influence of magmatic and post-magmatic processes on the distribution of uranium in igneous rocks and related ore deposits. Chapter 4 relates the results of experimental studies on the crystallization of granites to some of the geologic features of uranium deposits in pegmatites and alaskites in high-grade metamorphic terrains. Potential or favorable areas for igneous uranium deposits in the U.S.A. are delineated in Chapter 5. Data on the geology of specific uranium deposits in granitic rocks are contained in Appendix 1. A compilation of igneous rock formations containing greater than 10 ppM uranium is included in Appendix 2. Appendix 3 is a report on the results of a visit to the Roessing area. Appendix 4 is a report on a field excursion to eastern Canada

  13. Status of LLNL granite projects

    Energy Technology Data Exchange (ETDEWEB)

    Ramspott, L.D.

    1980-12-31

    The status of LLNL Projects dealing with nuclear waste disposal in granitic rocks is reviewed. This review covers work done subsequent to the June 1979 Workshop on Thermomechanical Modeling for a Hardrock Waste Repository and is prepared for the July 1980 Workshop on Thermomechanical-Hydrochemical Modeling for a Hardrock Waste Repository. Topics reviewed include laboratory determination of thermal, mechanical, and transport properties of rocks at conditions simulating a deep geologic repository, and field testing at the Climax granitic stock at the USDOE Nevada Test Site.

  14. Status of LLNL granite projects

    International Nuclear Information System (INIS)

    Ramspott, L.D.

    1980-01-01

    The status of LLNL Projects dealing with nuclear waste disposal in granitic rocks is reviewed. This review covers work done subsequent to the June 1979 Workshop on Thermomechanical Modeling for a Hardrock Waste Repository and is prepared for the July 1980 Workshop on Thermomechanical-Hydrochemical Modeling for a Hardrock Waste Repository. Topics reviewed include laboratory determination of thermal, mechanical, and transport properties of rocks at conditions simulating a deep geologic repository, and field testing at the Climax granitic stock at the USDOE Nevada Test Site

  15. Geochemical characteristics of Proterozoic granite magmatism from ...

    Indian Academy of Sciences (India)

    T Yellappa

    2018-03-06

    -type granites; Neoproterozoic .... morphosed carbonates, iron formations and pelites, all suggesting an ..... Table 2. Average concentrations of whole rock geochemistry of different granite plutons of the present study. Location.

  16. Granites petrology, structure, geological setting, and metallogeny

    CERN Document Server

    Nédélec, Anne; Bowden, Peter

    2015-01-01

    Granites are emblematic rocks developed from a magma that crystallized in the Earth’s crust. They ultimately outcrop at the surface worldwide. This book, translated and updated from the original French edition Pétrologie des Granites (2011) is a modern presentation of granitic rocks from magma genesis to their crystallization at a higher level into the crust. Segregation from the source, magma ascent and shapes of granitic intrusions are also discussed, as well as the eventual formation of hybrid rocks by mingling/mixing processes and the thermomechanical aspects in country rocks around granite plutons. Modern techniques for structural studies of granites are detailed extensively. Granites are considered in their geological spatial and temporal frame, in relation with plate tectonics and Earth history from the Archaean eon. A chapter on granite metallogeny explains how elements of economic interest are concentrated during magma crystallization, and examples of Sn, Cu, F and U ore deposits are presented. Mi...

  17. MORPHOMETRY OF ZIRCON FROM BETLIAR GRANITE

    Directory of Open Access Journals (Sweden)

    Jakabská Katarína

    1997-10-01

    Full Text Available Morphometrical analyse has been provided, using the method of [10] , on zircon from granite porphyry at Betliar. The result of this investigation indicate a comagmatic origin of Betliar and other granite bodies in the Gemericum. The source materila for at the granite magma formation originated by hybridization of crust-mantle rocks.

  18. Geochemical characteristics of Proterozoic granite magmatism from ...

    Indian Academy of Sciences (India)

    57

    Proterozoic A-type granites in parts of Madurai district, Tamil Nadu: Implications on uranium, rare earth, rare metal ... Key words: Southern Granulite Terrain, Cauvery Suture Zone, I-type and A-type granites, Neoproterozoic ...... I-S type characteristic in the Main Range Granite, Peninsular Malaysia; J. Asian Earth Sci.

  19. Radon exhalation from granitic rocks

    International Nuclear Information System (INIS)

    Del Claro, Flávia; Paschuk, Sergei A.; Corrêa, Janine N.; Mazer, Wellington; Narloch, Danielle Cristine; Martin, Aline Cristina; Denyak, Valeriy

    2017-01-01

    Naturally occurring radionuclides such as radon ( 222 Rn), its decay products and other elements from the radioactive series of uranium ( 238 U and 235 U) and thorium ( 232 Th) are an important source of human exposure to natural radioactivity. The worldwide evaluation of health radiobiological effects and risks from population exposure to natural radionuclides is a growing concern. About 50% of personal radiation annual dose is related to radionuclides such as radon ( 222 Rn), thoron ( 220 Rn), radium ( 226 Ra), thorium ( 232 Th) and potassium ( 40 K), which are present in modern materials commonly used in construction of dwellings and buildings. The radioactivity of marbles and granites is of big concern since under certain conditions the radioactivity levels of these materials can be hazardous to the population and require the implementation of mitigation procedures. Present survey of the 222 Rn and 220 Rn activity concentration liberated in the air was performed using commercialized Brazilian granite rocks at national market as well as exported to other countries. The 222 Rn and 220 Rn measurements were performed using the AlphaGUARD instant monitor and RAD7 detector, respectively. This study was performed at the Applied Nuclear Physics Laboratory of the Federal University of Technology – Paraná (UTFPR). Obtained results of radon concentration activity in air exhaled studied samples of granites varied from 3±1 Bq/m 3 to 2087±19 Bq/m 3 , which shows that some samples of granitic rocks represent rather elevated health risk the population. (author)

  20. Radon exhalation from granitic rocks

    Energy Technology Data Exchange (ETDEWEB)

    Del Claro, Flávia; Paschuk, Sergei A.; Corrêa, Janine N.; Mazer, Wellington; Narloch, Danielle Cristine; Martin, Aline Cristina [Universidade Tecnológica Federal do Paraná (UTFPR), Curitiba, PR (Brazil); Denyak, Valeriy, E-mail: flaviadelclaro@gmail.com, E-mail: spaschuk@gmail.com, E-mail: janine_nicolosi@hotmail.com, E-mail: denyak@gmail.com [Instituto de Pesquisa Pelé Pequeno Príncipe (IPPP), Curitiba, PR (Brazil)

    2017-07-01

    Naturally occurring radionuclides such as radon ({sup 222}Rn), its decay products and other elements from the radioactive series of uranium ({sup 238}U and {sup 235}U) and thorium ({sup 232}Th) are an important source of human exposure to natural radioactivity. The worldwide evaluation of health radiobiological effects and risks from population exposure to natural radionuclides is a growing concern. About 50% of personal radiation annual dose is related to radionuclides such as radon ({sup 222}Rn), thoron ({sup 220}Rn), radium ({sup 226}Ra), thorium ({sup 232}Th) and potassium ({sup 40}K), which are present in modern materials commonly used in construction of dwellings and buildings. The radioactivity of marbles and granites is of big concern since under certain conditions the radioactivity levels of these materials can be hazardous to the population and require the implementation of mitigation procedures. Present survey of the {sup 222}Rn and {sup 220}Rn activity concentration liberated in the air was performed using commercialized Brazilian granite rocks at national market as well as exported to other countries. The {sup 222}Rn and {sup 220}Rn measurements were performed using the AlphaGUARD instant monitor and RAD7 detector, respectively. This study was performed at the Applied Nuclear Physics Laboratory of the Federal University of Technology – Paraná (UTFPR). Obtained results of radon concentration activity in air exhaled studied samples of granites varied from 3±1 Bq/m{sup 3} to 2087±19 Bq/m{sup 3}, which shows that some samples of granitic rocks represent rather elevated health risk the population. (author)

  1. Thermal expansion behaviour of granites

    Czech Academy of Sciences Publication Activity Database

    Plevová, Eva; Vaculíková, Lenka; Kožušníková, Alena; Ritz, M.; Simha Martynková, G.

    2016-01-01

    Roč. 123, č. 2 (2016), s. 1555-1561 ISSN 1388-6150 R&D Projects: GA MŠk ED2.1.00/03.0082; GA MŠk(CZ) LO1406 Institutional support: RVO:68145535 Keywords : thermomechanical analysis * differential thermal analysis * granites Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.953, year: 2016 http://link.springer.com/article/10.1007/s10973-015-4996-z

  2. Natural radionuclide distribution in Brazilian commercial granites

    International Nuclear Information System (INIS)

    Anjos, R.M.; Veiga, R.; Soares, T.; Santos, A.M.A.; Aguiar, J.G.; Frasca, M.H.B.O.; Brage, J.A.P.; Uzeda, D.; Mangia, L.; Facure, A.; Mosquera, B.; Carvalho, C.; Gomes, P.R.S.

    2005-01-01

    The dimension stones sector in Brazil produces several varieties of granites, marbles, slates and basalts. More than half of this production corresponds to around 200 different commercial types of granites with specific names, geographical and geological origins and mineral compositions. The well-known natural radioactivity present in rocks, where high radiation levels are associated with igneous rocks such as granite, can be used to determine their general petrologic features. This subject is important in environmental radiological protection, since granites are widely used as building and ornamental stones. In this paper, it is applied to correlate the petrographic characteristics of commercial granites with their corresponding dose rates for natural radioactivity. Amounts of thorium, uranium and potassium concentrations have been reported in several Brazilian commercial granite samples

  3. Radionuclide migration through fractured granite

    International Nuclear Information System (INIS)

    Grondin, D.M.; Vandergraaf, T.T.; Drew, D.J.

    1988-01-01

    Radionuclide migration has been studied in natural fractures in granite blocks of up to 30 cm in length. Results are reported for four migration experiments involving synthetic groundwaters containing tritiated water, 95m Tc, 75 Se, 137 Cs, or 60 Co-labelled natural colloids, which were injected into the fractures at flow rates of 0.4-0.45 mL/h, giving residence times in the fractures of up to 15 h. Also presented are the results of the post-experiment analyses, including an autoradiograph of one of the fracture surfaces, and the spatial distribution of the sorbed radionuclides determined by γ-scanning and selective chemical extractions

  4. FROGS (Friends of Granites) report

    Science.gov (United States)

    Miller, Calvin

    This VGP News, which is devoted to petrology, is a good one for noting the existence of FROGS. FROGS is, as the name suggests, an informal organization of people whose research relates in one way or another to granitic rocks. Its purpose has been to promote communication among geoscientists with different perspectives and concerns about felsic plutonism. Initially, a major focus was experimental petrology and integration of field-oriented and lab-oriented viewpoints; now that there is the opportunity to communicate with the Eos readership, an obvious additional goal will be to bring together volcanic and plutonic views of felsic magmatism.FROGS first gathered in late 1982 under the guidance of E-an Zen and Pete Toulmin (both at U.S. Geological Survey (USGS), Reston, Va.), who saw a need for greater interaction among those interested in granites and for renewed, focused experimental investigations. They produced two newsletters (which were sent out by direct mail) and organized an informal meeting at the Geological Society of America meeting at Indianapolis, Ind., and then turned over the FROG reins to Sue Kieffer (USGS, Flagstaff, Ariz.) and John Clemens (Arizona State University, Tempe). They generated another newsletter, which was directly mailed to a readership that had grown beyond 200.

  5. Characterization of weathering profile in granites and ...

    Indian Academy of Sciences (India)

    Therefore, we propose three models describing the weathering profiles in granites, metasediments, and volcanic rocks for hard rock formations located in West Africa. For each of these models proposed for granitic and volcano sedimentary rocks of the Dimbokro catchment, vertical layered weathering profiles are described, ...

  6. Characterization of weathering profile in granites and ...

    Indian Academy of Sciences (India)

    In granitic rocks, various models of weathering profile have been proposed, but never for the hard rocks of West Africa. Besides, in the literature there is no description of the weathering profile in volcanosed- imentrary rocks. Therefore, we propose three models describing the weathering profiles in granites, metasediments ...

  7. Thermal expansion of granite rocks

    International Nuclear Information System (INIS)

    Stephansson, O.

    1978-04-01

    The thermal expansion of rocks is strongly controlled by the thermal expansion of the minerals. The theoretical thermal expansion of the Stripa Granite is gound to be 21 . 10 -6 [deg C] -1 at 25 deg C and 38 . 10 -6 [deg C] -1 at 400 deg C. The difference in expansion for the rock forming minerals causes micro cracking at heating. The expansion due to micro cracks is found to be of the same order as the mineral expansion. Most of the micro cracks will close at pressures of the order of 10 - 20 MPa. The thermal expansion of a rock mass including the effect of joints is determined in the pilot heater test in the Stripa Mine

  8. Automated tone grading of granite

    International Nuclear Information System (INIS)

    Catalina Hernández, J.C.; Fernández Ramón, G.

    2017-01-01

    The production of a natural stone processing plant is subject to the intrinsic variability of the stone blocks that constitute its raw material, which may cause problems of lack of uniformity in the visual appearance of the produced material that often triggers complaints from customers. The best way to tackle this problem is to classify the product according to its visual features, which is traditionally done by hand: an operator observes each and every piece that comes out of the production line and assigns it to the closest match among a number of predefined classes, taking into account visual features of the material such as colour, texture, grain, veins, etc. However, this manual procedure presents significant consistency problems, due to the inherent subjectivity of the classification performed by each operator, and the errors caused by their progressive fatigue. Attempts to employ automated sorting systems like the ones used in the ceramic tile industry have not been successful, as natural stone presents much higher variability than ceramic tiles. Therefore, it has been necessary to develop classification systems specifically designed for the treatment of the visual parameters that distinguish the different types of natural stone. This paper describes the details of a computer vision system developed by AITEMIN for the automatic classification of granite pieces according to their tone, which provides an integral solution to tone grading problems in the granite processing and marketing industry. The system has been designed to be easily trained by the end user, through the learning of the samples established as tone patterns by the user. [es

  9. Determination of dispersity of crushed granite

    International Nuclear Information System (INIS)

    Liu Dejun; Fan Xianhua; Zhang Yingjie; Yao Jun; Zhou Duo; Wang Yong

    2004-01-01

    The experimental crushed granite column breakthrough curves, using 99 Tc as spike tracer and 3 H as invariant tracer, are analyzed by different linear regression techniques. Dispersity of crushed granite and retardation factor of 99 TcO 4 - on the crushed granite are determined simultaneously by one linear regression technique. Dispersity of crushed granite is also obtained with 3 H as invariant tracer by the other linear regression technique. The dispersities found by spike source and invariant source methods are compared. The experimental results show that the dispersity found by spike source method is close to that found by invariant source method. It indicates that dispersity is only the characteristic of dispersion medium

  10. Determination of dispersity of crushed granite

    International Nuclear Information System (INIS)

    Liu, D.J.; Fan, X.H.

    2005-01-01

    Experimental crushed granite column breakthrough curves, using 99 Tc as spike tracer and 3 H as invariant tracer, were analyzed by different linear regression techniques. Dispersity of crushed granite and the retardation factor of 99 TcO 4 - on the crushed granite were determined simultaneously by one linear regression. Dispersity of crushed granite was also obtained with 3 H as invariant tracer by the other linear regression. The dispersities found by spike source and invariant source methods are compared. Experimental results show that the dispersity found by the spike source method is close to that found by the invariant source method. This indicates that dispersity is only a characteristic of the dispersion medium. (author)

  11. Rn-222 release to the environment: comparison between different granite sources

    International Nuclear Information System (INIS)

    Mamoon, M.; Kamal, S.M.

    2005-01-01

    In this work three different types of granites were studied, namely: pure granite, alkali granite and altered (hydrated) alkali granite. General radioactivity of the granites was studied along with the potential for 222 Rn emanation. The study indicated that altered alkali granite releases, relatively, the highest 222 Rn emanation to the surrounding air while alkali granite emits the more intense gamma radiation of the three granites. Hence, altered alkali granite can be used as a laboratory source for 222 Rn.

  12. Age of Pedra Branca granite (Goias) and possible geotectonic implications

    International Nuclear Information System (INIS)

    Marini, O.J.; Botelho, N.F.; Macambira, M.J.B.; Provost, A.

    1986-01-01

    Rb-Sr geochronologic dating of granites from the Pedra Branca Granite Massif (Nova Roma, Goias) shown an age of 1405 ± 21My. and a questionable initial Sr 87 /Sr 86 ratio of 0,7004 ± 0,006. Rhyolite from the base of the Arai Group is probably of the same age as the granitic intrusion. The 475 ± 19 My. age for the granitic intrusion is evidence of the Brasiliano Cycle imprint in Pedra Branca region. The age attributed to the Pedra Branca Granite is lower than known ages of the Goias tin granites giving rise to new geotectonic interpretations. It is possible that the Pedra Branca Granite represents a low-level intrusion emplaced at the beginning of structuration and deposition of the Arai basin. It may be correlated with granitic intrusions related to a rift stage above mantle hot spots, like the Nigerian tin younger granites. (author)

  13. Two contrasting granite types: 25 years later

    International Nuclear Information System (INIS)

    Chappell, B.W.; White, A.J.R.

    2001-01-01

    The concept of I- and S-type granites was introduced in 1974 to account for the observation that, apart from the most felsic rocks, the granites in the Lachlan Fold Belt have properties that generally fall into two distinct groups. This has been interpreted to result from derivation by partial melting of two kinds of source rocks, namely sedimentary and older igneous rocks. The original publication on these two granite types is reprinted and reviewed in the light of 25 years of continuing study into these granites. Data on oxygen isotopic compositions of the two granite types were not available in 1974. O'Neil and Chappell (1977) found differences in such composition between the I- and S-type granites of the Berridale Batholith, with the two types having δ 18 O values less than and greater than 10%o, respectively, relative to SMOW This division is supported by our additional unpublished data on granites from other parts of the Lachlan Fold Belt, but needs to be tested further. Chappell and White (1974) noted that the initial 87 Sr/ 86 Sr values for a single S-type pluton are more variable than for I-type plutons, interpreted to reflect the more heterogeneous nature of the source material. That observation has been confirmed by later observations. The heterogeneity of isotopic compositions of S-type plutons is illustrated by the Jillamatong Granodiorite of the Kosciuszko Batholith. For that single unit, the range in 87 Sr/ 86 Sr calculated at 430 Ma is from 0.71115 to 0.71541. Copyright (2001) Geological Society of Australia

  14. Performance assessment of alpha wastes disposal in deep geological formations, PACOMA project: granite option

    International Nuclear Information System (INIS)

    Brun-Yaba, C.; Cernes, A.; Mangin, J.P.

    1989-11-01

    After the CEC PAGIS project (for vitrified waste), the PACOMA project has been launched at the end of 1987 for cemented waste. The CEA-IPSN is in charge of the granite option. For the PACOMA project, a representative inventory of this type of waste has been built up, a repository concept (with one variant) has been defined and an adaptation of the near field module, Condiment, of the safety evaluation code MELODIE, has been made in order to take into account the particularities of cemented waste with respect to the vitrified waste. The best-estimate calculations have been performed on one reference site (the French Auriat Site) which is an outcropping granite and two variants, one representing a coastal granite formation (Barfleur) and the other, a granite with a sedimentary cover (notional British site). Moreover, the sensitivity and uncertainty analysis have been performed in the PACOMA project with a 2D modelling of the geosphere (module METIS of MELODIE code) instead of the 1D modelling (stream tube) previously used in the PAGIS project. After a general presentation of these points, the main results, namely the dose rates obtained through deterministic calculations, and the most important geosphere parameters, are presented [fr

  15. PREVALENCE OF METABOLIC SYNDROME IN GRANITE WORKERS

    Directory of Open Access Journals (Sweden)

    Srilakshmi

    2015-10-01

    Full Text Available BACKGROUND: The prevalence of the metabolic syndrome (MS has significantly increased over the last few decades and has become a main health challenge worldwide. Prevalence of MS is quickly rising in developing countries due to changing lifestyle. It was considered worthwhile to study MS and its components in granite workers since granite factories are situated in and around Khammam area. Moreover, no studies of MS in granite workers have been reported in literature. OBJECTIVES: Aim of our study is to assess the prevalence of metabolic syndrome and its components in granite workers. MATERIALS AND METHODS: 210 male workers in the age group of 20 - 50 working in granite industries located in and around the Khammam town of Telangana State are selected for the present study. Blood pressures (BP, waist circumference (WC were measured. Fasting blood samples were collected for the estimation of glucose and lipids. RESULTS: 69 subjects out of 210 were identified as having MS based on updated National cholesterol education programme - Adult Treatment Panel III (NCEP - ATP III guidelines. CONCLUSION: MS should be identified and remedial measures may be suggested, so that the risk of hypertension, cardiovascular risk, diabetes and the resultant morbidity is minimized and can be delayed

  16. Estimation of crystallization pressure of granite intrusions

    Science.gov (United States)

    Yang, Xue-Ming

    2017-08-01

    A numerical method is presented to estimate the crystallization pressure of granite intrusions based on two polynomial equations obtained by an analysis of the existing haplogranite ternary phase diagram and associated dataset. The results indicate that the pressure is correlated respectively with normative quartz (Qtz) content and with normative albite (Ab) plus orthoclase (Or) contents of granitic rocks as follows. where P is pressure in MPa, and R denotes correlation coefficient. It is noted that the procedure of normalizing the sum of CIPW norm (quartz, albite, orthoclase) contents to 100% is required before using Eqs. (1) and (2). The difference in pressure calculations between these two equations is ≤ 16 MPa for the range of normative quartz contents from 15 to 40 wt%. An example of how to use these equations to estimate the crystallization pressure of a granite intrusion is also provided to show the validity and convenience of this method. The uncertainty of such pressure estimation is not well known, although it must fall into the uncertainty range of the existing experimental work on pressure constraints. The simplicity of this empirical method is appreciable, although its applicability to natural granitoids needs further test. More experimental work is required to constrain the effects of components, such as CaO, FeO, MgO, F, Cl, CO2, on the granite phase equilibria. These equations, however, can be used for estimating crystallization pressures of water-saturated and quartz-oversaturated granitic systems.

  17. Geochemistry and petrogenesis of Proterozoic granitic rocks from ...

    Indian Academy of Sciences (India)

    granites, 5 pink granites and 7 porphyritic gran- ites) with least alteration and deformation were analysed for major oxides, trace elements and rare earth elements (table 1). The average chemical index of alteration (CIA) value of all samples is. 53, which lies within the accepted 45–55 range for unweathered granites (Nesbitt ...

  18. Tasmanian tin and tungsten granites - their radiometric characteristics

    International Nuclear Information System (INIS)

    Yeates, A.N.

    1982-01-01

    A radiometric survey of Tasmanian granites has shown, with one exception, that tin and tungsten-bearing granites have high radioactivity, largely owing to increased uranium. Many have a high uranium/thorium ratio as well. Radiometric measurements can also delineate different granite types within composite bodies

  19. Physics of the granite sphere fountain

    NARCIS (Netherlands)

    Snoeijer, Jacobus Hendrikus; van der Weele, J.P.

    2014-01-01

    A striking example of levitation is encountered in the “kugel fountain” where a granite sphere, sometimes weighing over a ton, is kept aloft by a thin film of flowing water. In this paper, we explain the working principle behind this levitation. We show that the fountain can be viewed as a giant

  20. Geochemical characteristics of Proterozoic granite magmatism from ...

    Indian Academy of Sciences (India)

    T Yellappa

    2018-03-06

    Mar 6, 2018 ... rocks occur near the transition zone around Krish- nagiri in the northern part of Tamil Nadu ... Archean and Neoproterozoic high-grade metamor- phic and magmatic rocks. The important ... Western Dharwar Craton, EDC: Eastern Dharwar Craton, Tz: Transition Zone. Location of the granite plutons are also.

  1. Characterization of weathering profile in granites and ...

    Indian Academy of Sciences (India)

    Characterization of weathering profile in granites and volcanosedimentary rocks in West Africa under humid tropical climate conditions. Case of the Dimbokro Catchment (Ivory Coast). M Koita1,2,∗, H Jourde1, K J P Koffi3, K S Da Silveira1 and A Biaou1. 1Water and Climate Research Center, International Institute for Water.

  2. Granite-hosted molybdenite mineralization from Archean ...

    Indian Academy of Sciences (India)

    discovered uranium content (Pathak et al. 2009) in the impact melt breccias of granitic compo- sition from Dhala structure (Pati et al. 2008a). The incidences of ...... affinity of the metal to felsic melts is expected. Isuk and Carman (1981) measured solubility of Mo in silicate melt and suggested that the metal is pos- sibly carried ...

  3. Landslides and the weathering of granitic rocks

    Science.gov (United States)

    Philip B. Durgin

    1977-01-01

    Abstract - Granitic batholiths around the Pacific Ocean basin provide examples of landslide types that characterize progressive stages of weathering. The stages include (1) fresh rock, (2) corestones, (3) decomposed granitoid, and (4) saprolite. Fresh granitoid is subject to rockfalls, rockslides, and block glides. They are all controlled by factors related to...

  4. Transpressional granite-emplacement model: Structural and ...

    Indian Academy of Sciences (India)

    the complete emplacement and deformation of the pluton during the Pan-African D2 and D3 events which occurred in the Pan-African belt in Cameroon and (2) reorganize Pan-African ages from Nguiessi. Tchakam et al. ... emplacement and deformation age of the granitic pluton in a dextral ENE–WSW shear movement. 1.

  5. Magma mixing in granite petrogenesis: Insights from biotite inclusions in quartz and feldspar of Mesozoic granites from South China

    Science.gov (United States)

    Gao, Peng; Zhao, Zi-Fu; Zheng, Yong-Fei

    2016-06-01

    Magma mixing is a common process in granite petrogenesis. The major element composition of biotites in granites is primarily controlled by the composition of magmas from which they crystallized. Biotite grains enclosed in quartz and feldspars of granites are naturally protected by their host minerals, so that their compositions are likely original and can potentially be used to track the magma mixing. This is illustrated by a combined study of matrix and inclusion biotites from Mesozoic granites in the Nanling Range, South China. Three granite samples have been used in this study: one two-mica granite and two biotite granites. The biotites of different occurrences in the two-mica granite have no compositional distinctions. Biotites in the two-mica granite have higher Al2O3 and lower MgO than those in the biotite granites. The former is consistent with biotites from typical S-type granites of metasedimentary origin. In contrast, biotites from the biotite granites can be categorized into different groups based on their paragenetic minerals and geochemical compositions. They have relatively low aluminous saturation indices but higher Mg numbers, falling in the transitional field between typical S- and I-type granites. In addition, there are two contrasting zircon populations with nearly identical U-Pb ages in the biotite granites. One shows clearly oscillatory zonings in CL images, whereas the other is totally dark and often overgrew on the former one. The zircons with oscillatory zonings have higher δ18O values than the dark ones, indicating their growth from two compositionally different magmas, respectively, with different sources. An integrated interpretation of all these data indicates that mixing of two different magmas was responsible for the petrogenesis of biotite granites. Therefore, the study of biotite inclusions provides insights into the magma mixing in granite petrogenesis.

  6. Fractal patterns of fractures in granites

    Science.gov (United States)

    Velde, B.; Dubois, J.; Moore, D.; Touchard, G.

    1991-01-01

    Fractal measurements using the Cantor's dust method in a linear one-dimensional analysis mode were made on the fracture patterns revealed on two-dimensional, planar surfaces in four granites. This method allows one to conclude that: 1. (1)|The fracture systems seen on two-dimensional surfaces in granites are consistent with the part of fractal theory that predicts a repetition of patterns on different scales of observation, self similarity. Fractal analysis gives essentially the same values of D on the scale of kilometres, metres and centimetres (five orders of magnitude) using mapped, surface fracture patterns in a Sierra Nevada granite batholith (Mt. Abbot quadrangle, Calif.). 2. (2)|Fractures show the same fractal values at different depths in a given batholith. Mapped fractures (main stage ore veins) at three mining levels (over a 700 m depth interval) of the Boulder batholith, Butte, Mont. show the same fractal values although the fracture disposition appears to be different at different levels. 3. (3)|Different sets of fracture planes in a granite batholith, Central France, and in experimental deformation can have different fractal values. In these examples shear and tension modes have the same fractal values while compressional fractures follow a different fractal mode of failure. The composite fracture patterns are also fractal but with a different, median, fractal value compared to the individual values for the fracture plane sets. These observations indicate that the fractal method can possibly be used to distinguish fractures of different origins in a complex system. It is concluded that granites fracture in a fractal manner which can be followed at many scales. It appears that fracture planes of different origins can be characterized using linear fractal analysis. ?? 1991.

  7. Portuguese granites associated with Sn-W and Au mineralizations

    OpenAIRE

    Ana M.R. Neiva

    2002-01-01

    In northern and central Portugal, there are different tin-bearing granites. Most of them are of S-type, others have mixed characteristics of I-type and S-type granites and a few are of I-type. Tin-tungsten deposits are commonly associated with Hercynian tin-bearing S-type granites. Some quartz veins with wolframite are associated with an I-type granite, which has a low Sn content. In suites of tin-bearing S-type granitic rocks, Sn content increases as a function of the degree of fractional cr...

  8. Paleo-redox boundaries in fractured granite

    DEFF Research Database (Denmark)

    Dideriksen, K.; Christiansen, B. C.; Frandsen, Cathrine

    2010-01-01

    At the Earth's surface, Fe(II) often oxidises and forms insoluble Fe(III)-(oxyhydr)oxides, whose particle size and structure depend on solution composition and temperature during formation and afterwards. Bacterial processes and exposure to reducing environments reduces them again, releasing....... In samples taken from similar to 120 m drill cores in granite from SE Sweden, X-ray amorphous, superparamagnetic, nanometre-sized Fe-oxides are confined to fractures of the upper,-,50 m, whereas well-crystalline Fe-oxides, with particle sizes typical for soils, occur down to similar to 110 m. We also...... that are not significantly altered, indicating formation during periods of oxidation. Our results show that oxygenated water may reach depths of similar to 110 m in fractured granite. The absence of natural, low-temperature Fe-oxides from deeper drill cores suggests that oxygenated waters do not readily penetrate beyond...

  9. Retention of Anionic Species on Granite: Influence of Granite Composition - 12129

    Energy Technology Data Exchange (ETDEWEB)

    Videnska, Katerina [Institute of Chemical Technology, Prague (Czech Republic); Havlova, Vaclava [Nuclear Research Institute Rez, Rez, 25068 (Czech Republic)

    2012-07-01

    Technetium (Tc-99, T{sub 1/2} = 2.1.10{sup 5} yrs) and selenium (Se-79, T{sub 1/2} = 6.5.10{sup 4} yrs) belong among fission products, being produced by fission of nuclear fuel. Both elements can significantly contribute to risk due to their complicated chemistry, long life times, high mobility and prevailing anionic character. Therefore, knowledge of migration behaviour under different conditions can significantly improve input into performance and safety assessment models. Granite is considered as a potential host rock for deep geological disposal of radioactive waste in many countries. Granitic rocks consist usually of quartz, feldspar, plagioclase (main components), mica, chlorite, kaolinite (minor components). The main feature of the rock is advection governed transport in fractures, complemented with diffusion process from fracture towards undisturbed rock matrix. The presented work is focused on interaction of anionic species (TcO{sub 4}{sup -}, SeO{sub 4}{sup 2-}, SeO{sub 3}{sup 2-}) with granitic rock. Furthermore, the importance of mineral composition on sorption of anionic species was also studied. The batch sorption experiments were conducted on the crushed granite from Bohemian Massive. Five fractions with defined grain size were used for static batch method. Mineral composition of each granitic fraction was evaluated using X-ray diffraction. The results showed differences in composition of granitic fractions, even though originating from one homogenized material. Sorption experiments showed influence of granite composition on adsorption of both TcO4{sup -} and SeO3{sup 2-} on granitic rock. Generally, Se(IV) showed higher retention than Tc(VII). Se(VI) was not almost sorbed at all. Fe containing minerals are pronounced as a selective Se and Tc sorbent, being reduced on their surface. As micas in granite are usually enriched in Fe, increased sorption of anionic species onto mica enriched fractions can be explained by this reason. On the other hand

  10. Coastal Engineering

    NARCIS (Netherlands)

    Van der Velden, E.T.J.M.

    1989-01-01

    Introduction, waves, sediment transport, littoral transport, lonshore sediment transport, onshore-offshore sediment transport, coastal changes, dune erosion and storm surges, sedimentation in channels and trenches, coastal engineering in practice.

  11. Natural radioactivity of granites used as building materials

    International Nuclear Information System (INIS)

    Pavlidou, S.; Koroneos, A.; Papastefanou, C.; Christofides, G.; Stoulos, S.; Vavelides, M.

    2006-01-01

    Sixteen kinds of different granites, used as building materials, imported to Greece mainly from Spain and Brazil, were sampled and their natural radioactivity was measured by gamma-ray spectrometry. The activity concentrations of 238 U, 226 Ra, 232 Th and 4 K of granites are presented and compared to those of other building materials as well as other granite types used all over the world. In order to assess the radiological impact from the granites investigated, the absorbed and the effective doses were determined. Although the annual effective dose is higher than the limit of 1 mSv y -1 for some studied granites, they could be used safely as building materials, considering that their contribution in most of the house constructions is very low. An attempt to correlate the relatively high level of natural radioactivity, shown by some of the granites, with their constituent radioactive minerals and their chemical composition, was also made

  12. Index of granitic rock masses in the state of Nevada

    Science.gov (United States)

    Maldonado, Florian; Spengler, Richard W.; Hanna, W.F.; Dixon, G.L.

    1988-01-01

    A compilation of 205 areas of exposed granitic rock in Nevada was undertaken for the U.S. Department of Energy. The purpose was to obtain data for evaluating granitic rock masses as potential underground nuclear waste repositories. Information, compiled by county for areas of granitic rock exposure, includes general location, coordinates, land classification, areal extent, accessibility, composition, age, rocks intruded, aeromagnetic expression, mining activity, and selected references.

  13. Rare-earth elements in granites: concentration and distribution pattern

    International Nuclear Information System (INIS)

    Galindo, A.C.

    1983-01-01

    The geochemistry of rare earth elements in granites is studied. The rare earth element (REE) distribution pattern in granites is characterized by a smooth curve with decreasing concentrations from La to Lu, and frequently a marked Eu negative anomaly. It seems to exist relationship between granite genesis and its REE pattern, in that bodies of primary (magmatic differentiation) origin always show this negative Eu anomaly, while those bodies generated by crustal anatexis do not show this anomaly. (E.G.) [pt

  14. Preface to special issue: Granite magmatism in Brazil

    Science.gov (United States)

    Janasi, Valdecir de Assis; de Pinho Guimarães, Ignez; Nardi, Lauro Valentim Stoll

    2016-07-01

    Granites are important both to the geologic evolution and to the economy of Brazil. Deposits of precious and rare metals, such as Au, Sn and many others, are directly or indirectly associated with granites, especially in the geologically under-explored Amazon region. On the opposite eastern side of the country, expanding exploitation of natural granite as dimension stone makes Brazil currently the world's second largest exporter of granite blocks. Granites are a major constituent of the Brazilian Archean-Proterozoic cratonic domains (the Amazon and São Francisco cratons) and their surrounding Neoproterozoic fold belts. The granites are thus fundamental markers of the major events of crustal generation and recycling that shaped the South American Platform. As a result, Brazilian granites have received great attention from the national and international community, and a number of influential meetings focused on the study of granites were held in the country in the last three decades. These meetings include the two International Symposia on Granites and Associated Mineralization (Salvador, January 21-31, 1987, and August 24-29, 1997), the Symposium on Rapakivi Granites and Related Rocks (Belém, August 2-5, 1995) and the Symposium on Magmatism, Crustal Evolution, and Metallogenesis of the Amazonian Craton (Belém, August 2006). Special issues dedicated to contributions presented at these meetings in the Journal of South American Earth Sciences (Sial et al., 1998), Lithos (Stephens et al., 1999), Canadian Mineralogist (Dall'Agnol and Ramo, 2006), Precambrian Research (Ramo et al., 2002) and Anais da Academia Brasileira de Ciências (Dall'Agnol and Bettencourt, 1997; Sial et al., 1999a) are still important references on the knowledge of Brazilian granites and granite petrology in general.

  15. A Bibliography on the Chemical Weathering of Granitic Rocks

    Science.gov (United States)

    1988-09-01

    Figuerda, H. 1970. (Observations of weathering a,d morphology of granitic blocks, El Roble Mountain). Revista Geografica de Valparaiso, vol. 4, pp. 64-68...weathering of granite. Geochimica et Cosmochimica Acta , vol. 48, pp. 1249-1255. Moeyersons, J. 1977. Joint patterns and their influence on the form of...transported quartz grains from the Harney Peak granite, Black Hills, South Dakota. Geochimica et Cosmochimica Acta , vol. 43, pp. 137-146. Pye, K. 1986

  16. Portuguese granites associated with Sn-W and Au mineralizations

    Directory of Open Access Journals (Sweden)

    Ana M.R. Neiva

    2002-01-01

    Full Text Available In northern and central Portugal, there are different tin-bearing granites. Most of them are of S-type, others have mixed characteristics of I-type and S-type granites and a few are of I-type. Tin-tungsten deposits are commonly associated with Hercynian tin-bearing S-type granites. Some quartz veins with wolframite are associated with an I-type granite, which has a low Sn content. In suites of tin-bearing S-type granitic rocks, Sn content increases as a function of the degree of fractional crystallization. Greisenizations of two-mica S-type granites associated with tin-tungsten mineralizations are accompanied by an increase in SiO2, H2O+, Sn, W, Nb, Ta, Rb, Zn, and Pb and decrease in MgO, Na2O, V, Sc,Zr, and Sr. The granite associated with the Jales gold deposit is of S-type and strongly differentiated like the tin-bearing S-type granites, but it has a very low Sn content. During fractional crystallization, Si, Rb, Sn, Pb, Au, As, Sb, and S increase. During increasing degree of hydrothermal alteration of this granite at the gold-quartz vein walls, there are progressive increases in K2O, H2O+, Sn, Cs, Cu, Pb, Au, Sb, As, and S.

  17. Characterization of mechanical damage in granite

    Directory of Open Access Journals (Sweden)

    Minh-Phong Luong

    2014-01-01

    Full Text Available This paper aims to illustrate the use of infrared thermography as a non-destructive and non-contact technique to observe the phenomenological manifestation of damage in granite under unconfined compression. It allows records and observations in real time of heat patterns produced by the dissipation of energy generated by plasticity. The experimental results show that this technique, which couples mechanical and thermal energy, can be used for illustrating the onset of damage mechanism by stress concentration in weakness zones.

  18. A combined geochronological approach to investigating long lived granite magmatism, the Shap granite, UK

    Science.gov (United States)

    Miles, A. J.; Woodcock, N. H.

    2018-04-01

    With the advent of more precise dating methods, it has become apparent that zircon dates from granite plutons frequently indicate older emplacement ages than other dating methods. Here we attempt to reconcile a number of dating methods from the c. 5 km2 Caledonian Shap granite, Northern England. The results reveal a more complex and protracted evolution than indicated by application of any single dating method. Zircon U-Pb dates give a weighted mean age of 415.6 ± 1.4 (2σ) Ma. A mafic enclave, dated at 412 ± 2 (2σ) Ma (revised Rb-Sr feldspar age from Davidson et al., 2005), contains resorbed K-feldspar and zircon crystals scavenged from the host crystal mush. These ages are at odds with field relations in the thermal aureole that suggest final emplacement at approximately 404 Ma or later during Acadian deformation. Previously reported Re-Os ages on molybdenites associated with magmatic fluids, have given ages of 405.2 ± 1.8 (2σ) Ma (Selby et al., 2008) and confirm the overlap of at least some magmatic activity with Acadian deformation. A similar emplacement age is supported by Rb-Sr whole-rock-mineral and biotite K-Ar dates when adjusted for revised decay constants (402 ± 3 Ma and 401 ± 7 Ma, respectively, Wadge et al., 1978). The lower closure temperatures of these systems relative to the U-Pb system in zircon means that they are more likely to record the timing of final granite emplacement. These data suggest that most zircons grew before final granite emplacement, by about 10 Ma on average. We suggest that the majority of zircon crystals record pre-emplacement magmatic activity within a deeper part of the system. Mafic enclaves and their scavenged cargo of crystals record the assembly of a mid-crustal batholith where crystals remained at least locally mobile at 412 Ma. Gravity data support the existence of an extensive, 1500 km2 intrusive body, originally at about 15 km depth beneath Shap. This batholith is likely to have remained below the granite

  19. Warren Hunt to test granite well

    International Nuclear Information System (INIS)

    Harvie, W.

    1996-01-01

    Various theories which purport to explain the existence of the Alberta oil sands, were discussed briefly. One theory, held among others by Warren Hunt, speculates that oil is formed deep in the Precambrian basement and not in the higher sedimentary rock. According to this theory, methane in the crust is the abiogenic product that results from hydrogen reacting with silicon carbide in the lower mantle. As it rises through the fractures, it encounters the microbiota, and hydrogen is stripped away making larger molecules until only bitumen remains. Hunt and other adherents of this theory believe that hydrocarbon reservoirs are replenished as oil is produced, hence there is no end to the world's oil supply. This theory is about to be tested by retesting a granite well near Fort McMurray, which was suspended in September 1994, when funding dried up. Kaleeda Enterprises, owners of the well, believe that the well bottom is currently in a granite pool, and oil will be found by deepening the well to 2,150 metres from the current 1,650 metres. While this is not universally accepted, if true, the abiogenic theory would go a long way towards explaining the origin of the oil sands

  20. The 'Granite' collegial mission of dialogue. Report

    International Nuclear Information System (INIS)

    Boisson, P.; Huet, Ph.; Mingasson, J.

    2000-06-01

    The aim of the 'Granite' collegial mission of dialogue is to inform the French authorities, associations and population about the project of construction of an underground laboratory for the study of the disposal of high level and long-life radioactive wastes in a granitic environment. The aim of the dialogue was not to select a site but to collect the public reactions and advices about such a project. However, such a dialogue has partially failed because of a misunderstanding of the population about the aims of the mission. However, the mission has collected many point of views and questions which are developed in this report. The first and second chapters recall the process of the mission and its progress, while a third chapter stresses on the questions asked by the public and which concern the fear of nuclear wastes and the incompatibility between the disposal of wastes and the socio-economical development of the region concerned. Thanks to the lessons drawn from this experience, the mission has formulated some recommendations (chapter 4) concerning the need for a better information of the population about any topic in relation with the radioactive wastes. Some complementary information is provided in appendixes. (J.S.)

  1. The Serra do Carambei Granite - PR and the uraniferous anomalism

    International Nuclear Information System (INIS)

    Pinto-Coelho, C.V.

    1986-01-01

    The Serra do Carambei Granite forms a pluton relatively homogeneous, covering about 33 km 2 , cropping out as an elongate retangular body trending NE-SW, being emplaced in the Cunhaporanga Granitoid Complex. Its characteristics indicates a kind of hololeucocratic granite, equigranular, medium to coarse-grained, consisting predominantly of microperthitic alkali-feldspar, quartz and a small amount of biotite (less than 1%), thus being classified as an alaskite. Chemical data allows a classification in the group of granite with high contents of silica (74-76% Wt. SiO 2 ), dominantly alkaline chemism and hypersolvus character, derived from a parental magma under saturated in water with distinguished features of granitoids from the magnetite series and types I and A granites. The pluton shows important chemical variations due to weathering processes. However detailed chemical studies reveal the presence of anomalous concentrations of trace elements such as U, Sn, Nb, Y, Zr, the Serra do Carambei Granite lacks economically important mineralizations because of the absence of well-developed tardi/pos-magmatic processes that could concentrate them. The SW side of the granite is cut by leucocratic rhyolite dykes that show some radiometric anomalies. These rocks, which are highly diferentiated, were emplaced contemporaneously to the Serra do Carambei Granite. Although petrographic and chronological similarities are found between the uraniferous alaskite of Roessing (Namibia) and the Serra do Carambei Granite anyhow it was not possible to establish any lateral continuity with the uranifeous Pan-African Province. (Author) [pt

  2. Geochemical study of volcanic and associated granitic rocks from ...

    Indian Academy of Sciences (India)

    and pyroclastic rocks are closely associated with granitic rock. In the south of Peninsular Malaysia, the volcanic rocks, especially the lava type, usually occur in close association with the I-type granitic rock. The study area is part of the Endau Rompin. National Park, Johor State, located in the south- ern part of Peninsular ...

  3. Effectiveness of granite cleaning procedures in cultural heritage: A review.

    Science.gov (United States)

    Pozo-Antonio, J S; Rivas, T; López, A J; Fiorucci, M P; Ramil, A

    2016-11-15

    Most of the Cultural Heritage built in NW Iberian Peninsula is made of granite which exposition to the environment leads to the formation of deposits and coatings, mainly two types: biological colonization and sulphated black crusts. Nowadays, another form of alteration derives from graffiti paints when these are applied as an act of vandalism. A deep revision needs to be addressed considering the severity of these deterioration forms on granite and the different cleaning effectiveness achieved by cleaning procedures used to remove them. The scientific literature about these topics on granite is scarcer than on sedimentary carbonate stones and marbles, but the importance of the granite in NW Iberian Peninsula Cultural Heritage claims this review centred on biological colonization, sulphated black crusts and graffiti on granite and their effectiveness of the common cleaning procedures. Furthermore, this paper carried out a review of the knowledge about those three alteration forms on granite, as well as bringing together all the major studies in the field of the granite cleaning with traditional procedures (chemical and mechanical) and with the recent developed technique based on the laser ablation. Findings concerning the effectiveness evaluation of these cleaning procedures, considering the coating extraction ability and the damage induced on the granite surface, are described. Finally, some futures research lines are pointed out. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Soil Radon In The Nigerian Younger Granites | Dewu | Nigerian ...

    African Journals Online (AJOL)

    ... not had enough time to attain equilibrium with its daughters. In general, the results suggest that with proper control, soil radon measurements over the Younger Granite can be used for uranium exploration in the region. Keywords: Radon, younger granite, soil uranium, half-lifeand thorium. Nigerian Journal of Physics Vol.

  5. Geochemistry and petrogenesis of Proterozoic granitic rocks from ...

    Indian Academy of Sciences (India)

    This study presents the geochemical characteristics of granitic rocks located on the northern margin of Chotanagpur Gneissic Complex (CGC), exposed in parts of Gaya district, Bihar and discusses thepossible petrogenetic process and source characteristics. These granites are associated with BarabarAnorthosite Complex ...

  6. Tectonic imprints within a granite exposed near Srinagar, Rajasthan ...

    Indian Academy of Sciences (India)

    We disentangle the deformation fabrics seen within the granite and associated DFB metasediments, suggesting that subsequent to emplacement and consolidation, the granite has co-folded along with the country rocks. Three deformational events could be identified within the DFB metasediments namely, D1D, D2D and ...

  7. Early Neoarchaean A-type granitic magmatism by crustal reworking ...

    Indian Academy of Sciences (India)

    29

    dyke swarm). It is suggested that the ~2.8 Ga A-type granites in the Singbhum craton mark a significant crustal reworking event attendant to mantle-derived mafic magmatism in an extensional tectonic setting. Key words: Granite; A-type; Geochemistry; Archaean; Crustal reworking; Singhbhum craton. Abstract. Click here to ...

  8. Early Neoarchaean A-type granitic magmatism by crustal reworking ...

    Indian Academy of Sciences (India)

    Abhishek Topno

    2018-04-11

    Apr 11, 2018 ... crustal melting of tonalitic/granodioritic source similar to the ~3.3 Ga Singhbhum Granite. Intrusion of the Pala Lahara granites was coeval with prominent mafic magmatism in the Singhbhum craton (e.g., the Dhanjori mafic volcanic rocks and NNE–SSW trending mafic dyke swarm). It is suggested that the.

  9. Geochemical study of volcanic and associated granitic rocks from ...

    Indian Academy of Sciences (India)

    The rare earth elements (REE) patterns of some of the granite and volcanic samples have pronounced negative Eu anomaly indicating plagioclase fractionation. The difference between both profiles is that the granite samples show a concave shape profile which is consistent with liquids produced by partial melting of quartz ...

  10. Adsorption behavior of Am(III) on granite

    International Nuclear Information System (INIS)

    Zhang Yingjie; Feng Xiaogui; Liang Junfu; Chen Jing; Su Rui; Wang Ju; Liu Chunli

    2009-01-01

    The adsorption behavior of Am(III) on granite (sampled from drilling well BS01 at Beishan (BS) area--a potential candidate site for China's high-level radioactive waste repository, the granite sample's depth about 300 m) was studied in BS03 well groundwater by a batch technique at (25±1) degree C. The influences of pH, sulphate ion, total carbonate ion, humic acid, and concentration of the Am(III) on the adsorption behavior were also studied, and the possible adsorption mechanism was discussed. Experimental results show that the adsorption distribution rate of Am(III) on granite increases with increasing pH of aqueous phase. The chemical composition of the groundwater is the main factor which influences the species of Am(III) and adsorption behavior. The adsorption mechanism of Am(III) on granite is surface complexation. The adsorption isotherm of Am(III) on granite can be described by Freundlich's equation. (authors)

  11. Chemical characteristics of zircon from A-type granites and comparison to zircon of S-type granites

    Czech Academy of Sciences Publication Activity Database

    Breiter, Karel; Lamarão, C. N.; Krás Borges, R. M.; Dall'Agnol, R.

    1192/195, April (2014), s. 208-225 ISSN 0024-4937 Institutional support: RVO:67985831 Keywords : zircon * A-type granites * S-type granites * Wiborg batholith * Brazil * Krušné hory/Erzgebirge Subject RIV: DD - Geochemistry Impact factor: 4.482, year: 2014

  12. Coastal Dynamics

    NARCIS (Netherlands)

    Roelvink, J.A.; Steetzel, H.J.; Bliek, A.; Rakhorst, H.D.; Roelse, P.; Bakker, W.T.

    1998-01-01

    This book deals on "Coastal Dynamics", which will be defined in a narrow sense as a mathematical theory, which starts from given equations of motion for the sediment, which leads with the continuity equation and given boundary conditions to a calculated (eventually schematized) coastal topography,

  13. Total exploitation of an ornamental granite quarry

    Directory of Open Access Journals (Sweden)

    Taboada, J.

    2005-09-01

    Full Text Available In this paper we propose a methodology to estimate the recovery percentage for each of the products which can be obtained from the exploitation of an ornamental granite quarry: block, semiblock, masonry-transverse stone, and the smaller materials that can be used to obtain construction aggregates. This methodology ensures that quarry exploitation is exhaustive, thereby minimising the production of spoils and the consequent negative impact on the environment. The analysis is based on a detailed and exhaustive compilation of discontinuity data from the research fronts, which are then interpreted statistically and projected over the three weakness planes that are a particular feature of ornamental granite deposits. Using this information, and bearing in mind the minimum commercially viable sizes for each kind of granite, the corresponding recovery rates are calculated for each material in each plane. The results are then integrated using spatial techniques, and the result is an evaluation of quarry contents with a view to total exploitation. This methodology was applied to a quarry in the opening phase in order to carry out an a priori assessment of the economic feasibility of the quarry.

    En este trabajo se propone una metodología para estimar el porcentaje de recuperación de cada uno de los productos que se pueden obtener en la explotación de una cantera de granito ornamental: bloque, semibloque, manpostería y per piaños, y material restante destinado a la obtención de áridos. De esta manera se logra un aprovechamiento integral de la cantera, evitándose la generación de estériles y el subsiguiente impacto ambiental producido por éstos. La metodología de análisis se basa en la recopilación detallada y exhaustiva de datos de discontinuidades en los frentes de investigación, que se interpretan estadísticamente y se proyectan sobre los tres planos de debilidad propios del granito ornamental. Con esta información, y las

  14. Radionuclide sorption on granitic drill core material

    International Nuclear Information System (INIS)

    Eriksen, T.E.; Locklund, B.

    1987-11-01

    Distribution ratios were determined for Sr-85, Cs-134 and Eu-152 on crushed granite and fissure coating/filling material from Stripa mines. Measurements were also carried out on intact fissure surfaces. The experimental data for Sr-85, Cs-134 on crushed material can be accomodated by a sorption model based on the assumption that the crushed material consists of porous spheres with outer and inner surfaces available for sorption. In the case of Eu-152 only sorption on the outer surfaces of the crushed material was observed. The absence of sorption on inner surfaces is most probably due to high depletion of the more strongly sorbed Eu-152 in the water phase and very low diffusivity of Eu-152 in the sorbed state. (orig./HP)

  15. Alkaline lixiviation of uranium in granitic pegmatite

    International Nuclear Information System (INIS)

    Jambor, S.

    1980-06-01

    The work described herein concerns the determination of the experimental optimum conditions for the alkaline lixiviation of uranium based on the following parameters: time, pH, temperature, density and grane size. The samples were obtained from the Supamo complex, near the Currupia river in the Piar District of the Bolivar State in Venezuela. They have a granitic composition and graphitic texture. The uranium was found in them as a secondary oxidized mineral of green-yellow colour localized in fractures fissures, intergranular spaces and also in the mica as. Secondary uranitite. The lixiviation process was carried out using Na 2 CO 3 /NaHCO 3 buffer solution and for 100 gr. samples the best values for an efficient process were found by using 170 mesh grane size and 500 ml of pH buffer at 70 0 C for a 24 hour time period. (author)

  16. Diffusion data in granite. Recommended values

    International Nuclear Information System (INIS)

    Ohlsson, Yvonne; Neretniks, I.

    1997-10-01

    Diffusion data for radionuclide transport in the porous matrix of rock are proposed for Swedish rock and ground waters, for performance assessment. Suggested data are based on an experimental diffusion study, where tritiated water was used as noninteracting diffusing species in stationary diffusion experiments in Aespoe fine grained granite and diorite. These data, for tritiated water, were used as reference in our study. For other species the effective diffusivities could be predicted from knowledge of the relative behaviour of these species to that of tritiated water. The behaviour is influenced by the difference in free water diffusivity and sometimes the existence of anion exclusion of surface diffusion. Apparent diffusivities are also calculated using sorption data, in addition to the effective diffusivities. Data are proposed for high saline and low saline ground water conditions

  17. Expected repository environments in granite: thermal environment

    International Nuclear Information System (INIS)

    Osnes, J.D.; Coates, G.K.; DeJong, K.B.; Loken, M.C.; Wagner, R.A.

    1984-10-01

    This report was prepared for the Reference Repository Conditions - Interface Working Group and will be used to formulate a standardized description of repository conditions for use by the Civilian Radioactive Waste Management Program. A baseline repository in granite is defined and three waste types are considered: unreprocessed spent fuel, commercial high-level waste, and defense high-level waste. Three different scales of repository environment are described - the very-near field (near the waste canister), the near field (the room and pillar), and the far field (the entire repository and surroundings). Information was compiled from the literature and, in addition, a number of calculations were performed. The major emphasis is on describing the thermal environment although the ground-water flow and chemical and radiation environments are also described. 61 figures, 24 tables

  18. Design of a dosimetric evaluation protocol workers granite quarries

    International Nuclear Information System (INIS)

    Guillen, J.; Tejado, J. J.; Baeza, A.

    2011-01-01

    The Autonomous Community of Extremadura is one of the major regions of Spain as far as the extraction of granite and further processing of products derived from it are concerned. One of the most industrialized areas of the sector presents a serious problem for non-radiological occupational health of workers, particularly silicosis. Since in this area of activity levels of granites can be classified as medium-high within the precipitates ranges, the question is whether in addition to this occupational disease, there is a radiological impact associated with the activity NORM extraction and manufacturing of granite.

  19. 2005 dossier: granite. Tome: phenomenological evolution of the geologic disposal; Dossier 2005: Granite. Tome evolution phenomenologique du stockage geologique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This document makes a status of the researches carried out by the French national agency of radioactive wastes (ANDRA) about the phenomenological aspects of the geologic disposal of high-level and long-lived radioactive wastes (HLLL) in granite formations. Content: 1 - introduction: ANDRA's research program on disposal in granitic formation; 2 - the granitic environment: geologic history, French granites; 3 - HLLL wastes and disposal design concepts; 4 - identification, characterization and modeling of a granitic site: approach, geologic modeling, hydrologic and hydro-geochemical modeling, geomechanical and thermal modeling, long-term geologic evolution of a site; 5 - phenomenological evolution of a disposal: main aspects of the evolution of a repository with time, disposal infrastructures, B-type wastes disposal area, C-type wastes disposal area; spent fuels disposal area, radionuclides transfer and retention in the granitic environment; 6 - conclusions: available knowledge, methods and tools for the understanding and modeling of the phenomenological evolution of a granitic disposal site. (J.S.)

  20. Mechanical properties of granitic rocks from Gideaa, Sweden

    International Nuclear Information System (INIS)

    Ljunggren, C.; Stephansson, O.; Alm, O.; Hakami, H.; Mattila, U.

    1985-10-01

    The elastic and mechanical properties were determined for two rock types from the Gideaa study area. Gideaa is located approximately 30 km north-east of Oernskoeldsvik, Northern Sweden. The rock types that were tested were migmatitic gneiss and migmatitic granite. The following tests were conducted: - sound velocity measurements; - uniaxial compression tests with acoustic emission recording; - brazilian disc tests; - triaxial tests; - three point bending tests. All together, 12 rock samples were tested with each test method. Six samples of these were migmatic gneiss and six samples were migmatitic granite. The result shows that the migmatitic gneiss has varying strength properties with low compressive strength in comparison with its high tensile strength. The migmatitic granite, on the other hand, is found to have parameter values similar to other granitic rocks. With 15 refs. (Author)

  1. Geochemistry of Pegmatites associated with the cape coast granite ...

    African Journals Online (AJOL)

    Geochemistry of Pegmatites associated with the cape coast granite complex in the Egyaa and Akim Oda areas of southern Ghana. PM Nude, JEK Hanson, SB Dampare, TT Akiti, S Osae, ES Nyarko, N Zkaria, S Enti-Brown ...

  2. Radioactivity and radon emanation fraction of the granites sampled at Misasa and Badgastein.

    Science.gov (United States)

    Sakoda, Akihiro; Hanamoto, Katsumi; Ishimori, Yuu; Nagamatsu, Tomohiro; Yamaoka, Kiyonori

    2008-05-01

    The chemical composition was analyzed and the radioactivity, radon exhalation rate and emanation fraction were measured to investigate the characteristics of the granites sampled at Misasa and Badgastein, world famous for radon therapy. The Misasa granite was probably composed of quartz, albite and microcline. The Badgastein granite was probably composed of quartz and muscovite. The radon exhalation rates and emanation fractions of the Misasa granite were much higher than those of the Badgastein granite, regardless of the (226)Ra activity concentrations.

  3. Granite-related hypothermal uranium mineralization in South China

    International Nuclear Information System (INIS)

    Liu, X.; Wu, J.; Pan, J.; Zhu, M.

    2014-01-01

    As one of the important geological types, granite-related uranium deposits account for about 29% of the total discovered natural uranium resources in China. Most of the granite-related uranium deposits located in Taoshan - Zhuguang uranium metallogenic belt, South China. In addition to the typical pitchblende vein-type uranium mineralization of epithermal metallogenic system, a new type of granite-related uranium mineralization with characteristics of hypothermal matallogenic system was discovered in South China by current studies. However, hypothermal is contact thermal to epithermal mineralization, and not the conventional intrusive high temperature mineralization. Hypothermal uranium mineralization is presented by disseminated uraninite or pitchblende stockwork in fissures in granites normally with extensive alkaline alteration. The high temperature mineral assemblage of uraninite associate with scheelite and tourmaline was identified in hypothermal uranium mineralization. Fluid inclusion studies on this type mineralization indicated the middle to high temperature (>250℃) mineralization with the mixing evidence of ore forming solution derived from deep level, and the boiling and mixing of ore forming solution are regarded as the dominant mineralization mechanism for the precipitating of uranium. In contrast to the mineralization ages of 67 Ma to 87 Ma for typical pitchblende vein mineralization of epithermal metallogenic system, the mineralization age is older than 100 Ma for hypothermal uranium mineralization in granite. In the Shituling deposit, Xiazhuang uranium ore field, uraninite and pitchblende micro veins with extensive potassic alteration, chloritization and sericitization are hosted in fissures of Indo-Chinese epoch granites with the uranium mineralization age of 130 Ma to 138 Ma with a mineralization temperature of 290℃ to 330℃ indicated. Other examples sharing the similar characters of hypothermal uranium mineralization have been recognized in

  4. Radionuclide Transport in Fracture-Granite Interface Zones

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Mori, A

    2007-09-12

    In situ radionuclide migration experiments, followed by excavation and sample characterization, were conducted in a water-conducting shear zone at the Grimsel Test Site (GTS) in Switzerland to study diffusion paths of radionuclides in fractured granite. In this work, we employed a micro-scale mapping technique that interfaces laser ablation sampling with inductively coupled plasma-mass spectrometry (LA/ICP-MS) to measure the fine-scale (micron-range) distribution of actinides ({sup 234}U, {sup 235}U, and {sup 237}Np) in the fracture-granite interface zones. Long-lived {sup 234}U, {sup 235}U, and {sup 237}Np were detected in flow channels, as well as in the adjacent rock matrix, using the sensitive, feature-based mapping of the LA/ICP-MS technique. The injected sorbing actinides are mainly located within the advective flowing fractures and the immediately adjacent regions. The water-conducting fracture studied in this work is bounded on one side by mylonite and the other by granitic matrix regions. These actinides did not penetrate into the mylonite side as much as the relatively higher-porosity granite matrix, most likely due to the low porosity, hydraulic conductivity, and diffusivity of the fracture wall (a thickness of about 0.4 mm separates the mylonite region from the fracture) and the mylonite region itself. Overall, the maximum penetration depth detected with this technique for the more diffusive {sup 237}Np over the field experimental time scale of about 60 days was about 10 mm in the granitic matrix, illustrating the importance of matrix diffusion in retarding radionuclide transport from the advective fractures. Laboratory tests and numerical modeling of radionuclide diffusion into granitic matrix was conducted to complement and help interpret the field results. Measured apparent diffusivity of multiple tracers in granite provided consistent predictions for radionuclide transport in the fractured granitic rock.

  5. Uranium occurrences in the Granite Zone

    International Nuclear Information System (INIS)

    Nyegaard, P.; Armour-Brown, A.

    1986-04-01

    This report describes the work and results of the South Greenland Exploration Programme (Sydex) during the 1984 field season in the Granite Zone, and discusses the results and conclusions that can be drawn from them. It also contains a structural analysis of the Ivigtut-Julianehaab region, which will help in future exploration by indicating the likely directions of uraniferous faults and fractures. It also includes suggestions for future work with both exploration and scientific aspects. The project was carried out by the Geological Survey Greenland (GGU) in co-operation with Risoe National Laboratory. It was financed by the Danish Ministry of Energy. The structural analysis was carried out using previous geological maps, our own field observations and an analysis of lineament frequencies taken from aerial photographs and satellite images. Major lineaments in the region are due to E-W sinistral wrench faults and NE-SW normal faults. Analysis of the minor lineaments showed that the region could be divided into three blocks which have each reacted differently to the same regional stress field which was active throughout the Gardar period. A northern block which has been influenced by an older system of faults in the Archaean gneiss, a central block dominated by a graben, and a southern block where there is a change to a less intensively faulted area. 2 maps, 27 refs. (EG)

  6. Heat transfer studies in salt and granite

    International Nuclear Information System (INIS)

    Just, R.A.

    1978-10-01

    Results are presented of a scoping study on the feasibility of using a multi-layer terminal repository design in both salt and granite formations to store either high-level waste or spent fuel. Calculations have been made to determine temperature profiles within the repository and to provide an estimate of the thermal uplift that can be expected. Near-field models developed to compare temperature profiles in the regions close to the waste canisters indicated that maximum thermal gradients and maximum temperature increases could be significantly reduced by changing from a single to a multi-layer repository design. For both high-level waste and for spent fuel, the maximum temperature increase in the multi-level repositories was reduced to approximately 60 percent of the temperature increase predicted for the single-level repositories at the same areal loading. After the near-field models had verified that maximum thermal gradients and temperature increases could be reduced by using a multilevel repository design, a series of far-field models was developed. The far-field models used to provide qualitative comparisons of the maximum thermal uplift indicate that the thermal uplift is roughly proportional to the energy supplied to the formation. Changing from a single- to a multi-layer repository but keeping the areal loading constant results in increased thermal uplifts

  7. Groundwater evolution of the granite area, Korea

    International Nuclear Information System (INIS)

    Kim, C.S.; Bae, D.S.; Koh, Y.K.; Kim, K.S.; Kim, G.Y.

    2001-01-01

    The geochemistry and environmental isotopes of groundwater in the Cretaceous granite of the Yeongcheon area has been investigated. The hydrochemistry of groundwater belongs to the Ca-HCO 3 type. The oxygen-18 and deuterium data are clustered along the meteoric water line, indicating that the groundwater is of meteoric water origin. Tritium data show that the groundwaters were mostly recharged before pre-thermonuclear period and have been mixed with younger surface water flowing rapidly along fractured zones. Based on the mass balance and reaction simulation approaches using both the hydrochemistry of groundwater and the secondary mineralogy of fracture-filling materials, the low-temperature hydrogeochemical evolution of groundwater in the area has been modeled. The results of geochemical simulation show that the concentrations of Ca, Na and HCO 3 and pH of waters increase progressively owing to the dissolution of reactive minerals in flow paths. The concentrations of Mg and K first increase with the dissolution of reactant minerals, but later decrease when montmorillonite and illitic material are precipitated respectively. The continuous adding of reactive minerals, i. e. the progressively larger degrees of water/rock interaction, causes the formation of secondary minerals with the following sequence: hematite > gibbsite > kaolinite > montmorillonite > illitic material > microcline. The results of reaction simulation agree well with the observed water chemistry and secondary mineralogy, indicating the successful applicability of this simulation technique to delineate the complex hydrogeochemistry of bedrock groundwaters. (author)

  8. Long-term rocky coast erosion: the influence of structural pattern and lithological context, as evidenced in the chalk (NW Normandy) and granitic (SW Brittany) rocks, NW France

    Science.gov (United States)

    Duperret, Anne; Raimbault, Céline; Duguet, Timothée; Le Gall, Bernard; Costa, Stéphane; Vandycke, Sara

    2017-04-01

    During the EC2CO/DRIL/CROCODYL project, high-resolution land-sea DEM have been produced in NW Normandy and SW Brittany rocky coastal zone, using high-resolution bathymetry from shallow-water cruises CROCOLIT-1,-2,-3 (Duperret, 2013), SPLASHALIOT-3 (Maillet, 2014), THAPENFROM-1 (Duperret, 2015) and aerial topographic LiDAR data from the Litto3D project. Two study sites were selected to map detailed geomorphology of shore platforms in order to better understand rock coast evolution processes through time and long-term rates of rocky coastal erosion versus geological context. The eastern English Channel is made of coastal chalk cliffs that currently eroding with fast mean rates of the order of a few dm/year. In Normandy coast (NW France), this results to the generation of roughly linear coastal segments of about 20-30km long each. On coastal segments only made of Upper Cretaceous Chalk, erosion occurs by present-day sudden and repeated vertical failures and cliff collapses. Cliff collapse process is shaping vertical chalk cliffs in association with resulting roughly flat shore platforms. Even if shore platforms width are short and homogeneous (a few hundred meters in width), the detailed morphology observed on high-resolution bathymetry evidenced two main submarine geomorphological types. One is linear and regular and associated with linear coastal sections. This corresponds to homogeneous Chalk Formation and the lack of large-scale tectonic features. Coastal sections with chalk lithology variations, local folding, large-scale fractures transverse-oriented to the coastline and onshore valleys incision evidence chaotic shore platforms morphologies. They conduct to variations in coastline orientation and to meter-scale shoreline indentations The southwestern part of Brittany is made of low-lying granitic headland and indented bay cut into meta/granitic rocks. Erosion rates are poorly known, due to slow coastal evolutions through contemporary times. Land-Sea DEM evidence

  9. Smolt Monitoring at the Head of Granite Reservoir and Lower Granite Dam, 1989 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Nelson, V. Lance

    1990-04-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha and steelhead trout O. mykiss smolts during the 1989 spring outmigration at a migrant trap on the Snake River and the Clearwater River. Chinook salmon catch at the Snake River trap was much higher in 1989 than in either of the 1987 or 1988 drought years. The 1989 Snake River trap catch was similar to 1986. Effort was the same during the four years. Steelhead trout catch was greater than in any previous year. Chinook salmon and steelhead trout catch at the Clearwater River trap was similar to 1986, even though effort was greatly reduced in 1989 due to high runoff during most of the season. The 1989 Clearwater River trap catch was lower than in the two drought years (1987 and 1988) and was due to the minimal number of days the trap was operated. Fish tagged with Passive Interrogated Transponder (PIT) tags at the Snake River trap were recovered at the three dams (Lower Granite, Little Goose, and McNary) with PIT tag detection systems. Travel time (days) and migration rate (km/d) through Lower Granite Reservoir for PIT-tagged chinook salmon and steelhead trout, marked at the head of the reservoir, was affected by discharge. Statistical analysis showed that as discharge increased from 40 kcfs to 80 kcfs, chinook salmon travel time decreased three-fold and steelhead trout travel time decreased two-fold. 11 refs., 8 figs., 17 tabs.

  10. The 'Granite' collegial mission of dialogue. Report; Mission collegiale de concertation Granite. Rapport

    Energy Technology Data Exchange (ETDEWEB)

    Boisson, P.; Huet, Ph.; Mingasson, J

    2000-06-01

    The aim of the 'Granite' collegial mission of dialogue is to inform the French authorities, associations and population about the project of construction of an underground laboratory for the study of the disposal of high level and long-life radioactive wastes in a granitic environment. The aim of the dialogue was not to select a site but to collect the public reactions and advices about such a project. However, such a dialogue has partially failed because of a misunderstanding of the population about the aims of the mission. However, the mission has collected many point of views and questions which are developed in this report. The first and second chapters recall the process of the mission and its progress, while a third chapter stresses on the questions asked by the public and which concern the fear of nuclear wastes and the incompatibility between the disposal of wastes and the socio-economical development of the region concerned. Thanks to the lessons drawn from this experience, the mission has formulated some recommendations (chapter 4) concerning the need for a better information of the population about any topic in relation with the radioactive wastes. Some complementary information is provided in appendixes. (J.S.)

  11. Coastal zone

    International Nuclear Information System (INIS)

    2002-01-01

    The report entitled Climate Change Impacts and Adaptation : A Canadian Perspective, presents a summary of research regarding the impacts of climate change on key sectors over the past five years as it relates to Canada. This chapter on the coastal zone focuses on the impact of climate change on Canada's marine and Great Lakes coasts with tips on how to deal with the impacts associated with climate change in sensitive environments. This report is aimed at the sectors that will be most affected by adaptation decisions in the coastal zone, including fisheries, tourism, transportation and water resources. The impact of climate change in the coastal zone may include changes in water levels, wave patterns, storm surges, and thickness of seasonal ice cover. The Intergovernmental Panel on Climate Change projects global average sea level will rise between 9 and 88 centimetres between 1990 to 2100, but not all areas of Canada will experience the same rate of future sea level change. The main physical impact would be shoreline change that could result in a range of biophysical and socio-economic impacts, some beneficial, some negative. The report focuses on issues related to infrastructure and communities in coastal regions. It is noted that appropriate human adaptation will play a vital role in reducing the extent of potential impacts by decreasing the vulnerability of average zone to climate change. The 3 main trends in coastal adaptation include: (1) increase in soft protection, retreat and accommodation, (2) reliance on technology such as geographic information systems to manage information, and (3) awareness of the need for coastal adaptation that is appropriate for local conditions. 61 refs., 7 figs

  12. U(VI) sorption on granite: prediction and experiments

    International Nuclear Information System (INIS)

    Nebelung, C.; Brendler, V.

    2010-01-01

    One widely accepted approach - component additivity (CA) - to describe the sorption of contaminants onto complex materials such as rocks or soils is based on the assumption that the surface of a complex mineral assemblage is composed of a mixture of mineral constituents whose surface properties are known from independent studies. An internally consistent SCM (surface complexation model) database can be developed that describes the adsorption reactions of solutes to each phase. Here, the capability of such a methodology was tested, using the code MINTEQA2 including thermodynamic data of the NEA-TDB, and literature data for SCM, namely the DDL model. The sorption characteristics of U(VI) on granite (from Eibenstock, Saxony, Germany, with the main components quartz, albite, orthoclase, and muscovite) was predicted and then compared to batch experiments. Granite plays an important role in the remediation of former uranium ore mining and milling sites, but is also one of the host rocks considered for final disposal of nuclear materials. Safety assessment requires a detailed understanding of this system and its retention potential with regard to hazardous components. Namely the sorption of uranium in this complex rock is not fully understood yet. The experiments thus also provided a better understanding of the far-field behaviour in granitic geological nuclear repositories. The robustness of the prediction was tested by variation of the granite composition and the variation of the specific surface area (SSA) - first all components were predicted with a uniform granite SSA, second with a distinct SSA for each granite component (determined on pure minerals for the same grain size fractions). Changes in compositions yielded only marginal differences in the prediction. Different approaches to SSA showed somewhat larger deviations. In conclusion, the CA methodology is a valid and robust approach to U(VI) sorption onto complex substrates such as granite, provided sufficient

  13. Thermomechanical studies in granite at Stripa, Sweden

    International Nuclear Information System (INIS)

    Cook, N.G.W.; Myer, L.R.

    1981-01-01

    Media other than rock salt are being considered for the deep, geologic disposal of nuclear wastes. The disposal of high-level nuclear waste in a deep, underground repository will subject the rock to a thermal pulse that will induce displacements, strains, and stresses in the rock. Thermomechanical experiments, with electrical heaters simulating the thermal output of waste canisters, were carried out in granite at a depth of 340 m below surface adjacent to a defunct iron ore mine at Stripa, Sweden. Changes in temperature, displacement, and stress in the rock around these heaters were measured, and the measurements were compared with predictions calculated from the theory of linear thermoelasticity. Measured temperature changes agreed well with predictions, but measured displacements and stresses were consistently less than those predicted with constant values for the coefficient of thermal expansion and elastic properties of the rock. A laboratory test program to measure these coefficients over ranges of stress and temperature representing those in the field experiment has been initiated. Test specimens were taken from cores recovered from the instrumentation holes in the Stripa experiments. Preliminary results from laboratory tests on specimens free of joints indicate that the values of Young's modulus and Poisson's ratio increase from about 60 to 80 MPa and from 0.15 to 0.22, respectively, as the confining stress is increased from 2 to 55 MPa; these values decrease with increasing temperature, more so at 2 MPa than at 55 MPa. The linear coefficient of thermal expansion at a confining stress of 30 MPa increases from about 10 x 10 - 6 / 0 C at 40 0 C to about 14 x 10 - 6 / 0 C. The magnitudes of these changes are not sufficient to resolve the disparity between measured and predicted results. Perhaps the properties of test specimens containing joints will show greater variations in the values of the thermomechanical coefficients with temperature and pressure

  14. Determination of Matrix Diffusion Properties of Granite

    International Nuclear Information System (INIS)

    Holtta, Pirkko; Siitari-Kauppi, Marja; Huittinen, Nina; Poteri, Antti

    2007-01-01

    Rock-core column experiments were introduced to estimate the diffusion and sorption properties of Kuru Grey granite used in block-scale experiments. The objective was to examine the processes causing retention in solute transport through rock fractures, especially matrix diffusion. The objective was also to estimate the importance of retention processes during transport in different scales and flow conditions. Rock-core columns were constructed from cores drilled into the fracture and were placed inside tubes to form flow channels in the 0.5 mm gap between the cores and the tube walls. Tracer experiments were performed using uranin, HTO, 36 Cl, 131 I, 22 Na and 85 Sr at flow rates of 1-50 μL.min -1 . Rock matrix was characterized using 14 C-PMMA method, scanning electron microscopy (SEM), energy dispersive X-ray micro analysis (EDX) and the B.E.T. method. Solute mass flux through a column was modelled by applying the assumption of a linear velocity profile and molecular diffusion. Coupling of the advection and diffusion processes was based on the model of generalised Taylor dispersion in the linear velocity profile. Experiments could be modelled applying a consistent parameterization and transport processes. The results provide evidence that it is possible to investigate matrix diffusion at the laboratory scale. The effects of matrix diffusion were demonstrated on the slightly-sorbing tracer breakthrough curves. Based on scoping calculations matrix diffusion begins to be clearly observable for non-sorbing tracer when the flow rate is 0.1 μL.min -1 . The experimental results presented here cannot be transferred directly to the spatial and temporal scales that prevail in an underground repository. However, the knowledge and understanding of transport and retention processes gained from this study is transferable to different scales from laboratory to in-situ conditions. (authors)

  15. Coastal Structures

    DEFF Research Database (Denmark)

    Oumeraci, H.; Burcharth, H. F.; Rouck, J. De

    1995-01-01

    The paper attempts to present an overview of five research projects supported by the Commission of the European Communities, Directorate General XII, under the MAST 2- Programme (Marine Sciences and Technology), with the overall objective of contributing to the development of improved rational me...... methods for the design of coastal structures....

  16. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Putnam, Scott A. [Idaho Department of Fish and Game

    2009-02-18

    This project monitored the daily passage of Chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon O. nerka smolts during the 2005 spring out-migration at migrant traps on the Snake River and Salmon River. In 2005 fish management agencies released significant numbers of hatchery Chinook salmon and steelhead trout above Lower Granite Dam that were not marked with a fin clip or coded-wire tag. Generally, the age-1 and older fish were distinguishable from wild fish by the occurrence of fin erosion. Age-0 Chinook salmon are more difficult to distinguish between wild and non-adclipped hatchery fish and therefore classified as unknown rearing. The total annual hatchery spring/summer Chinook salmon catch at the Snake River trap was 0.34 times greater in 2005 than in 2004. The wild spring/summer Chinook catch was 0.34 times less than the previous year. Hatchery steelhead trout catch was 0.67 times less than in 2004. Wild steelhead trout catch was 0.72 times less than the previous year. The Snake River trap collected 1,152 age-0 Chinook salmon of unknown rearing. During 2005, the Snake River trap captured 219 hatchery and 44 wild/natural sockeye salmon and 110 coho salmon O. kisutch of unknown rearing. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with flow. Trap operations began on March 6 and were terminated on June 3. The trap was out of operation for a total of one day due to heavy debris. FPC requested that the trap be restarted on June 15 through June 22 to collect and PIT tag age-0 Chinook salmon. Hatchery Chinook salmon catch at the Salmon River trap was 1.06 times greater and wild Chinook salmon catch was 1.26 times greater than in 2004. The hatchery steelhead trout collection in 2005 was 1.41 times greater and wild steelhead trout collection was 1.27 times greater than the previous year. Trap operations

  17. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Putnam, Scott A. [Idaho Department of Fish and Game

    2009-02-18

    This project monitored the daily passage of Chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon O. nerka smolts during the 2004 spring out-migration at migrant traps on the Snake River and Salmon River. In 2004 fish management agencies released significant numbers of hatchery Chinook salmon and steelhead trout above Lower Granite Dam that were not marked with a fin clip or coded-wire tag. Generally, these fish were distinguishable from wild fish by the occurrence of fin erosion. Total annual hatchery Chinook salmon catch at the Snake River trap was 1.1 times greater in 2004 than in 2003. The wild Chinook catch was 1.1 times greater than the previous year. Hatchery steelhead trout catch was 1.2 times greater than in 2003. Wild steelhead trout catch was 1.6 times greater than the previous year. The Snake River trap collected 978 age-0 Chinook salmon of unknown rearing. During 2004, the Snake River trap captured 23 hatchery and 18 wild/natural sockeye salmon and 60 coho salmon O. kisutch of unknown rearing. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with flow. Trap operations began on March 7 and were terminated on June 4. The trap was out of operation for a total of zero days due to mechanical failure or debris. Hatchery Chinook salmon catch at the Salmon River trap was 10.8% less and wild Chinook salmon catch was 19.0% less than in 2003. The hatchery steelhead trout collection in 2004 was 20.0% less and wild steelhead trout collection was 22.3% less than the previous year. Trap operations began on March 7 and were terminated on May 28 due to high flows. There were two days when the trap was taken out of service because wild Chinook catch was very low, hatchery Chinook catch was very high, and the weekly quota of PIT tagged hatchery Chinook had been met. Travel time (d) and migration rate (km

  18. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Putnam, Scott A. [Idaho Department of Fish and Game

    2009-02-18

    This project monitored the daily passage of Chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon smolts O. nerka during the 2002 spring out-migration at migrant traps on the Snake River and Salmon River. In 2002 fish management agencies released significant numbers of hatchery Chinook salmon and steelhead trout above Lower Granite Dam that were not marked with a fin clip or coded-wire tag. Generally, these fish were distinguishable from wild fish by the occurrence of fin erosion. Total annual hatchery Chinook salmon catch at the Snake River trap was 11.4 times greater in 2002 than in 2001. The wild Chinook catch was 15.5 times greater than the previous year. Hatchery steelhead trout catch was 2.9 times greater than in 2001. Wild steelhead trout catch was 2.8 times greater than the previous year. The Snake River trap collected 3,996 age-0 Chinook salmon of unknown rearing. During 2002, the Snake River trap captured 69 hatchery and 235 wild/natural sockeye salmon and 114 hatchery coho salmon O. kisutch. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with flow. The significant increase in catch in 2002 was due to a 3.1 fold increase in hatchery Chinook production and a more normal spring runoff. Trap operations began on March 10 and were terminated on June 7. The trap was out of operation for a total of four days due to mechanical failure or debris. Hatchery Chinook salmon catch at the Salmon River trap was 4.2 times greater and wild Chinook salmon catch was 2.4 times greater than in 2001. The hatchery steelhead trout collection in 2002 was 81% of the 2001 numbers. Wild steelhead trout collection in 2002 was 81% of the previous year's catch. Trap operations began on March 10 and were terminated on May 29 due to high flows. The trap was out of operation for four days due to high flow or debris. The

  19. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Putnam, Scott A. [Idaho Department of Fish and Game

    2009-02-18

    This project monitored the daily passage of Chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon O. nerka smolts during the 2003 spring out-migration at migrant traps on the Snake River and Salmon River. In 2003 fish management agencies released significant numbers of hatchery Chinook salmon and steelhead trout above Lower Granite Dam that were not marked with a fin clip or coded-wire tag. Generally, these fish were distinguishable from wild fish by the occurrence of fin erosion. Total annual hatchery Chinook salmon catch at the Snake River trap was 2.1 times less in 2003 than in 2002. The wild Chinook catch was 1.1 times less than the previous year. Hatchery steelhead trout catch was 1.7 times less than in 2002. Wild steelhead trout catch was 2.1 times less than the previous year. The Snake River trap collected 579 age-0 Chinook salmon of unknown rearing. During 2003, the Snake River trap captured five hatchery and 13 wild/natural sockeye salmon and 36 coho salmon O. kisutch of unknown rearing. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with flow. The significant differences in catch between 2003 and the previous year were due mainly to low flows during much of the trapping season and then very high flows at the end of the season, which terminated the trapping season 12 days earlier than in 2002. Trap operations began on March 9 and were terminated on May 27. The trap was out of operation for a total of zero days due to mechanical failure or debris. Hatchery Chinook salmon catch at the Salmon River trap was 16.8% less and wild Chinook salmon catch was 1.7 times greater than in 2002. The hatchery steelhead trout collection in 2003 was 5.6% less than in 2002. Wild steelhead trout collection was 19.2% less than the previous year. Trap operations began on March 9 and were terminated on May 24 due to high

  20. A hot spring in granite of the Western Tianshan, China

    International Nuclear Information System (INIS)

    Bucher, Kurt; Zhang Lifei; Stober, Ingrid

    2009-01-01

    The western Tianshan range is a major Cenozoic orogenic belt in central Asia exposing predominantly Paleozoic rocks including granite. Ongoing deformation is reflected by very rugged topography with peaks over 7000 m high. Active tectonic deformation is tied to an E-W trending fracture and fault system that sections the mountain chain into geologically diverse blocks that extend parallel to the orogen. In the Muzhaerte valley upwelling hot water follows such a fault system in the Muza granite. About 20 L min -1 Na-SO 4 -Cl water with a temperature of 55 deg. C having a total mineralization of about 1 g L -1 discharge from the hot spring. The water is used in a local spa that is frequented by the people of the upper Ili river area. Its waters are used for balneological purposes and the spa serves as a therapeutic institution. The major element composition of the hot water is dominated by Na and by SO 4 and Cl, Ca is a minor component. Dissolved silica (1.04 mmol L -1 ) corresponds to a quartz-saturation temperature of 116 deg. C and a corresponding depth of the source of the water of about 4600 m. This temperature is consistent with Na/K and Na/Li geothermometry. The water is saturated with respect to fluorite and contains 7.5 mg L -1 F - as a consequence of the low Ca-concentration. The water is undersaturated with respect to the primary minerals of the reservoir granite at reservoir temperature causing continued irreversible dissolution of granite. The waters are oversaturated with respect to Ca-zeolite minerals (such as stilbite and mesolite), and it is expected that zeolites precipitate in the fracture pore space and in alteration zones replacing primary granite. The stable isotope composition of O and H supports a meteoric origin of the water. The Cl/Br mass ratio of 1500 suggests that the salinity results from halite dissolution. Salts leached from powders of Muza granite show the same Cl/Br signature as the hot spring water. Sodium chloride is stored in fluid

  1. The instrumental neutron-activation analysis of granites from the Bushveld Complex

    International Nuclear Information System (INIS)

    Watterson, J.I.W.

    1978-01-01

    Three methods of instrumental neutron-activation analysis, 14MeV, reactor thermal, and reactor epithermal, are compared for the analysis of granites form the Bushveld Complex. A total of 34 elements can be determined in the granites by these methods. Samples from the Zaaiplaats area were analysed by thermal neutron activation, and 22 elements were determined in all of them. These elements were used to distinguish between the mineralized Bobbejaankop and Lease granites and the Main granite by the use of multivariate statistics. The Bobbejaankop granite appears as a more-differentaited rock carrying greater amounts of the incompatible elements than does the Main granite [af

  2. Uranium distribution in Brazilian granitic rocks. Identification of uranium provinces

    International Nuclear Information System (INIS)

    Tassinari, C.G.G.

    1993-01-01

    The research characterized and described uranium enriched granitoids in Brazil. They occur in a variety of tectonic environments and are represented by a variety granite types of distinct ages. It may be deduced that in general they have been generated by partial melting process of continental crust. However, some of them, those with tonality composition, indicate a contribution from mantle derived materials, thus suggesting primary uranium enrichment from the upper mantle. Through this study, the identification and characterization of uranium enriched granite or uranium provinces in Brazil can be made. This may also help identify areas with potential for uranium mineralization although it has been note that uranium mineralization in Brazil are not related to the uranium enrichment process. In general the U-anomalous granitoids are composed of granites with alkaline composition and granite ''sensu strictu'' which comprise mainly of syenites, quartz-syenites and biotite-hornblende granites, with ages between 1,800 - 1,300 M.a. The U-anomalous belongings to this period present high Sr initial ratios values, above 0.706, and high Rb contents. Most of the U-enriched granitoids occur within ancient cratonic areas, or within Early to Mid-Proterozoic mobile belts, but after their cratonization. Generally, these granitoids are related to the border zones of the mobile belts or deep crustal discontinuity. Refs, 12 figs, 3 tabs

  3. Earth's youngest exposed granite and its tectonic implications: the 10-0.8 Ma Kurobegawa Granite.

    Science.gov (United States)

    Ito, Hisatoshi; Yamada, Ryuji; Tamura, Akihiro; Arai, Shoji; Horie, Kenji; Hokada, Tomokazu

    2013-01-01

    Although the quest for Earth's oldest rock is of great importance, identifying the youngest exposed pluton on Earth is also of interest. A pluton is a body of intrusive igneous rock that crystallized from slowly cooling magma at depths of several kilometers beneath the surface of the Earth. Therefore, the youngest exposed pluton represents the most recent tectonic uplift and highest exhumation. The youngest exposed pluton reported to date is the Takidani Granodiorite (~ 1.4 Ma) in the Hida Mountain Range of central Japan. Using LA-ICP-MS and SHRIMP U-Pb zircon dating methods, this study demonstrates that the Kurobegawa Granite, also situated in the Hida Mountain Range, is as young as ~ 0.8 Ma. In addition, data indicate multiple intrusion episodes in this pluton since 10 Ma with a ~ 2-million-year period of quiescence; hence, a future intrusion event is likely within 1 million years.

  4. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 1994 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Brimmer, Arnold F.

    1994-10-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha and steelhead trout O. mykiss smolts during the 1994 spring outmigration at migrant traps on the Snake River, Clearwater River, and Salmon River. The 1994 snowpack was among the lowest since the beginning of the present drought, and the subsequent runoff was very poor. All hatchery chinook salmon released above Lower Granite Dam were marked with a fin clip in 1994. Total annual (hatchery + wild) chinook salmon catch at the Snake River trap was 1.5 times greater than in 1993. Hatchery and wild steelhead trout catches were similar to 1993. The Snake River trap collected 30 age 0 chinook salmon. Hatchery chinook salmon catch at the Clearwater River trap was 3.5 times higher than in 1993, and wild chinook salmon catch was 4.2 times higher. Hatchery steelhead trout trap catch was less than half of 1993 numbers because the trap was fishing near the north shore during the majority of the hatchery steelhead movement due to flow augmentations from Dworshak. Wild steelhead trout trap catch was 2 times higher than in 1993. The Salmon River trap was operated for about a month longer in 1994 than in 1993 due to extremely low flows. Hatchery chinook salmon catch was 1.4 times greater in 1994 than the previous year. Wild chinook salmon catch was slightly less in 1994. The 1994 hatchery steelhead trout collection did not change significantly from 1993 numbers. Wild steelhead trout collection in 1994 was 59% of the 1993 catch. Fish tagged with Passive Integrated Transponder (PIT) tags at the Snake River trap were interrogated at four dams with PIT tag detection systems (Lower Granite, Little Goose, Lower Monumental, and McNary dams). Because of the addition of the fourth interrogation site (Lower Monumental) in 1993, cumulative interrogation data is not comparable with the prior five years (1988-1992).

  5. Radiatives elements distribution in Serra do Carambei granite, Parana, Brazil

    International Nuclear Information System (INIS)

    Pinto-Coelho, C.V.; Siedlecki, K.N.

    1988-01-01

    In the Serra do Carambei Granite, the uranium present in the rock in anomalous concentration is hosted, preferentially, in accessory mineralogical phases-zircon, xenotime, magnetite and ilmenite, and, in lesser proportion, in the essential minerals of the rock-potassium feldspar and also iron oxydes/hydroxydes and alterated biotite. Optical petrography, autorradiomicrography, scanning electronic microscopy, and the utilization of correlation matrixes and the respective dendrograms revealed a distribution of radioactive elements basically controlled by autometassomatic, tardi/pos-magmatic or supergene processes. Intrusive felsic dikes in the Serra do Carambei Granite have radioelement concentration level approximately four times higher than the enclosing granite, where uranium as well as thorium is preferentially found in metamictized accessory minerals-zircon and allanite. (author) [pt

  6. GRANITE CUTTING WASTE: TECHNOLOGICAL INNOVATION FOR THE FINAL DESTINATION

    Directory of Open Access Journals (Sweden)

    Joner Oliveira Alves

    2015-06-01

    Full Text Available The granite processing market is one of the most promising business areas of the mineral sector, with an average growth of the world production of about 6% per year. The granite extraction generates residues in the form of powder rock of 20-25 wt.% of the total benefited. The granite dust must be carefully managed since it can cause siltation of rivers and human health risks. This paper presents two routes for the final destination of this waste: the vitrification process aiming the production of fibers for thermo-acoustic insulation, and the magnetic separation in order to recover the steel grit. Results showed that the forms of treatments presented are economically and ecologically viable since they represent a cost reduction in the waste disposal, and also provide the production of new materials with commercial value.

  7. Analysis of Shield Construction in Spherical Weathered Granite Development Area

    Science.gov (United States)

    Cao, Quan; Li, Peigang; Gong, Shuhua

    2018-01-01

    The distribution of spherical weathered bodies (commonly known as "boulder") in the granite development area directly affects the shield construction of urban rail transit engineering. This paper is based on the case of shield construction of granite globular development area in Southern China area, the parameter control in shield machine selection and shield advancing during the shield tunneling in this special geological environment is analyzed. And it is suggested that shield machine should be selected for shield construction of granite spherical weathered zone. Driving speed, cutter torque, shield machine thrust, the amount of penetration and the speed of the cutter head of shield machine should be controlled when driving the boulder formation, in order to achieve smooth excavation and reduce the disturbance to the formation.

  8. Association of lung cancer mortality with precambrian granite

    International Nuclear Information System (INIS)

    Archer, V.E.

    1987-01-01

    Sixteen counties in New York, Pennsylvania, and New Jersey that are associated with the Reading Prong granite deposits have significantly higher age-adjusted lung cancer rates among whites of both sexes (1950-1979) than do 17 nearby control counties. Elevated radon daughter concentrations have been found in homes near the Reading Prong granites. Fraction of populations living in cities with over 5,000 persons, industrial centers, cities with populations above 20,000, and median incomes did not differ significantly for three county groups (those which include the granite, fringe area, and control areas). Weaknesses were inadequate home measurements of radon and lack of smoking information. Findings are consistent with several other studies relating radon in homes to lung cancer

  9. Transpressional granite-emplacement model: Structural and magnetic study of the Pan-African Bandja granitic pluton (West Cameroon)

    Science.gov (United States)

    Sandjo, A. F. Yakeu; Njanko, T.; Njonfang, E.; Errami, E.; Rochette, P.; Fozing, E.

    2016-02-01

    The Pan-African NE-SW elongated Bandja granitic pluton, located at the western part of the Pan-African belt in Cameroon, is a K-feldspar megacryst granite. It is emplaced in banded gneiss and its NW border underwent mylonitization. The magmatic foliation shows NE-SW and NNE-SSW strike directions with moderate to strong dip respectively in its northern and central parts. This mostly, ferromagnetic granite displays magnetic fabrics carried by magnetite and characterized by (i) magnetic foliation with best poles at 295/34, 283/33 and 35/59 respectively in its northern, central and southern parts and (ii) a subhorizontal magnetic lineation with best line at 37/8, 191/9 and 267/22 respectively in the northern, central and southern parts. Magnetic lineation shows an `S' shape trend that allows to (1) consider the complete emplacement and deformation of the pluton during the Pan-African D 2 and D 3 events which occurred in the Pan-African belt in Cameroon and (2) reorganize Pan-African ages from Nguiessi Tchakam et al. (1997) compared with those of the other granitic plutons in the belt as: 686 ±17 Ma (Rb/Sr) for D 1 age of metamorphism recorded in gneiss; and the period between 604-557 Ma for D 2-D 3 emplacement and deformation age of the granitic pluton in a dextral ENE-WSW shear movement.

  10. Granite microcracks: Structure and connectivity at different depths

    Science.gov (United States)

    Song, Fan; Dong, Yan-Hui; Xu, Zhi-Fang; Zhou, Peng-Peng; Wang, Li-Heng; Tong, Shao-Qing; Duan, Rui-Qi

    2016-07-01

    Granite is one rock type used to host high-level radioactive waste repositories, and the structure of microcracks in the rock can influence its hydraulic characteristics. Thus, a quantitative analysis of granite microcracks is relevant for understanding the hydrogeological characteristics of the rocks surrounding geological repositories. The analysis can also contribute scientific data to a seepage model for low permeability rocks and materials with microscopic pores. In this study, seven granite core samples were drilled from different depths up to 600 m in Alxa, Inner Mongolia, China. Using a grid survey method and image processing technology, micrographs were converted into binary images of microcracks. The geometric parameters of the microcracks, including their quantity, width, cranny ratio, crack intersections and dimensional parameters of the fracture network, were analyzed in order to fully describe their spatial distribution. In addition, the morphological characteristics and elemental compositions of the microcracks were analyzed by scanning electron microscopy energy dispersive X-ray analysis (SEM-EDS), and the natural moisture content was also determined through heated. Finally, two-dimensional microcrack network seepage models of the granite samples were simulated using the Lattice Boltzmann method (LBM), which revealed the influence of the microcrack structure on their connectivity. The results show that the growth and development of microcracks in the granite samples generally decreases as sampling depth increases in this study area. Connectivity is positively correlated with a number of the geometric parameters: the quantity of microcracks, the cranny ratio, the number of crack intersections and dimensional parameters of the fracture network, which is revealed in the two-dimensional microcrack network seepage models for these granite samples.

  11. Coastal resuspension

    International Nuclear Information System (INIS)

    Garland, J.A.

    1991-11-01

    There are several potential mechanisms for the suspension in air of radioactive or other pollutants from coastal sea water, beaches, mud banks and salt marshes. Available measurements rarely allow these mechanisms to be distinguished. The limited data show a broad spread of results. When normalised by the concentration of radionuclides in beach sediments most of the data indicate concentrations equivalent to 1 to 30 μg m -3 of sediment suspended in air, both for sampling sites on open coasts and near estuaries. Limited evidence for sampling sites located on salt marshes indicates about 0.2 μg m -3 of suspended sediment. These values represent the aggregate effect of the mechanisms that operate at a limited number of coastal locations. At other locations it is possible that additional mechanisms will contribute to the suspension of sediment. (Author)

  12. The Swedish Bohus granite - a stone with a fascinating history

    Science.gov (United States)

    Schouenborg, Björn; Eliasson, Thomas

    2015-04-01

    One of the most well-known and well spread Swedish stone types used as building stones is the Bonus granite. It outcrops in an area north of Gothenburgh (SW Sweden), along the coastline, approximately 35 km wide and 85 km long. The granite continues into Norway as the Iddefjord granite. The Bohus granite is one of Sweden's youngest granites. Isotopic dating shows that the magma cooled at about 920 M years ago and thus marking the end of the Sveconorwegian orogoney. It is a composite granite massif area with several granitic intrusions but with rather homogeneous mineralogy. However, colour and texture varies quite a lot and the colour ranges from red to reddish grey although some pure grey varieties occur sparsely. The grain size ranges from medium grained to coarse grained and even with some porphyric parts. Quarrying in an industrial scale started 1842. The merchant A C Kullgren opened the first quarry and produced stones for the construction of the 86 km long Trollhättan channel connecting lake Vänern and the Atlantic ocean in the SW Sweden The stone was used for constructing harbors and wharves along the channel. Several quarries opened in the late 1800 around 1870 - 1890 and the export increased steadily with deliveries to Germany, Denmark, Holland, England and even to South America. The stone industries in Bohuslän (Bohus county), at its peak in 1929, engaged around 7 000 employees. During the depression in 1930 almost all of them became unemployed. However, as a curiosity, production and export continued to Germany for construction of Germania, the future World capital city ("Welthauptstadt Germania"), planned by Adolf Hitler and Albert Speer. About 500 stone workers were kept employed for this project during the late thirties. Today several varieties are still produced: Evja/Ävja, Tossene, Brastad, Näsinge, Broberg, Nolby, Allemarken and Skarstad. However, the number of stone workers is far from that of the early 1900. The Swedish production is mainly

  13. Genesis of a zoned granite stock, Seward Peninsula, Alaska

    Science.gov (United States)

    Hudson, Travis

    1977-01-01

    A composite epizonal stock of biotite granite has intruded a diverse assemblage of metamorphic rocks in the Serpentine Hot Springs area of north-central Seward Peninsula, Alaska. The metamorphic rocks include amphibolite-facies orthogneiss and paragneiss, greenschist-facies fine-grained siliceous and graphitic metasediments, and a variety of carbonate rocks. Lithologic units within the metamorphic terrane trend generally north-northeast and dip moderately toward the southeast. Thrust faults locally juxtapose lithologic units in the metamorphic assemblage, and normal faults displace both the metamorphic rocks and some parts of the granite stock. The gneisses and graphitic metasediments are believed to be late Precambrian in age, but the carbonate rocks are in part Paleozoic. Dating by the potassium-argon method indicates that the granite stock is Late Cretaceous. The stock has sharp discordant contacts, beyond which is a well-developed thermal aureole with rocks of hornblende hornfels facies. The average mode of the granite is 29 percent plagioclase, 31 percent quartz, 36 percent K-feldspar, and 4 percent biotite. Accessory minerals include apatite, magnetite, sphene, allanite, and zircon. Late-stage or deuteric minerals include muscovite, fluorite, tourmaline, quartz, and albite. The stock is a zoned complex containing rocks with several textural facies that are present in four partly concentric zones. Zone 1 is a discontinuous border unit, containing fine- to coarse-grained biotite granite, that grades inward into zone 2. Zone 2 consists of porphyritic biotite granite with oriented phenocrysts of pinkish-gray microcline in a coarse-grained equigranular groundmass of plagioclase, quartz, and biotite. It is in sharp, concordant to discordant contact with rocks of zone 3. Zone 3 consists of seriate-textured biotite granite that has been intruded by bodies of porphyritic biotite granite containing phenocrysts of plagioclase, K-feldspar, quartz, and biotite in an

  14. Late Triassic granites from Bangka, Indonesia: A continuation of the Main Range granite province of the South-East Asian Tin Belt

    Science.gov (United States)

    Ng, Samuel Wai-Pan; Whitehouse, Martin J.; Roselee, Muhammad H.; Teschner, Claudia; Murtadha, Sayed; Oliver, Grahame J. H.; Ghani, Azman A.; Chang, Su-Chin

    2017-05-01

    The South-East Asian Tin Belt is one of the most tin-productive regions in the world. It comprises three north-south oriented granite provinces, of which the arc-related Eastern granite province and the collision-related Main Range granite province run across Thailand, Singapore, and Indonesia. These tin-producing granite provinces with different mineral assemblages are separated by Paleo-Tethyan sutures exposed in Thailand and Malaysia. The Eastern Province is usually characterised by granites with biotite ± hornblende. Main Range granites are sometimes characterised by the presence of biotite ± muscovite. However, the physical boundary between the two types of granite is not well-defined on the Indonesian Tin Islands, because the Paleo-Tethyan suture is not exposed on land there. Both hornblende-bearing (previously interpreted as I-type) and hornblende-barren (previously interpreted as S-type) granites are apparently randomly distributed on the Indonesian Tin Islands. Granites exposed on Bangka, the largest and southernmost Tin Island, no matter whether they are hornblende-bearing or hornblende-barren, are geochemically similar to Malaysian Main Range granites. The average ɛNd(t) value obtained from the granites from Bangka (average ɛNd(t) = -8.2) falls within the range of the Main Range Province (-9.6 to -5.4). These granites have SIMS zircon U-Pb ages of ca. 225 Ma and ca. 220 Ma, respectively that are both within the period of Main Range magmatism (∼226-201 Ma) in the Peninsular Malaysia. We suggest that the granites exposed on Bangka represent the continuation of the Main Range Province, and that the Paleo-Tethyan suture lies to the east of the island.

  15. 76 FR 62758 - Wallowa-Whitman and Umatilla National Forests, Oregon Granite Creek Watershed Mining Plans

    Science.gov (United States)

    2011-10-11

    ... Granite Creek Watershed Mining Plans AGENCY: Forest Service, USDA. ACTION: Notice of intent to prepare an... to authorize the approval of mining Plans of Operation in the Granite Creek Watershed Mining Plans... environmental analyses for proposed mining Plans in the portions of the Granite Creek Watershed under their...

  16. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 1998 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Brimmer, Arnold F.

    2000-04-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon smolts O. nerka, during the 1998 spring outmigration at migrant traps on the Snake and Salmon rivers. All hatchery chinook salmon released above Lower Granite Dam 19 1998 were marked with a fin-clip. Total annual hatchery chinook salmon catch at the Snake River trap was 226% of the 1997 number and 110% of the 1996 catch. The wild chinook catch was 120% of the 1997 catch but was only 93% of 1996. Hatchery steelhead trout catch was 501% of 1997 numbers but only 90% of the 1996 numbers. Wild steelhead trout catch was 569% of 1997 and 125% of the 1996 numbers. The Snake River trap collected 106 age-0 chinook salmon. During 1998, for the first time, the Snake River trap captured a significant number of hatchery sockeye salmon (1,552) and hatchery coho salmon O. kisutch (166). Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with high flows. Trap operations began on March 8 and were terminated for the season due to high flows on June 12. The trap was out of operation for 34 d during the season due to high flow and debris. Hatchery chinook salmon catch at the Salmon River trap was 476% and wild chinook salmon catch was 137% of 1997 numbers and 175% and 82% of 1996 catch, respectively. The hatchery steelhead trout collection in 1998 was 96% of the 1997 catch and 13% of the 1996 numbers. Wild steelhead trout collection in 1998 was 170% of the 1997 catch and 37% of the 1996 numbers. Travel time (d) and migration rate (km/d) through Lower Granite Reservoir for PIT-tagged chinook salmon and steelhead trout, marked at the head of the reservoir were affected by discharge. For fish tagged at the Snake River trap, statistical analysis of 1998 detected a significant relation between migration rate and discharge. For hatchery and

  17. Smolt monitoring at the head of Lower Granite Reservoir and Lower Granite Dam, 1998.; ANNUAL

    International Nuclear Information System (INIS)

    2000-01-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon smolts O. nerka, during the 1998 spring outmigration at migrant traps on the Snake and Salmon rivers. All hatchery chinook salmon released above Lower Granite Dam 19 1998 were marked with a fin-clip. Total annual hatchery chinook salmon catch at the Snake River trap was 226% of the 1997 number and 110% of the 1996 catch. The wild chinook catch was 120% of the 1997 catch but was only 93% of 1996. Hatchery steelhead trout catch was 501% of 1997 numbers but only 90% of the 1996 numbers. Wild steelhead trout catch was 569% of 1997 and 125% of the 1996 numbers. The Snake River trap collected 106 age-0 chinook salmon. During 1998, for the first time, the Snake River trap captured a significant number of hatchery sockeye salmon (1,552) and hatchery coho salmon O. kisutch (166). Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with high flows. Trap operations began on March 8 and were terminated for the season due to high flows on June 12. The trap was out of operation for 34 d during the season due to high flow and debris. Hatchery chinook salmon catch at the Salmon River trap was 476% and wild chinook salmon catch was 137% of 1997 numbers and 175% and 82% of 1996 catch, respectively. The hatchery steelhead trout collection in 1998 was 96% of the 1997 catch and 13% of the 1996 numbers. Wild steelhead trout collection in 1998 was 170% of the 1997 catch and 37% of the 1996 numbers. Travel time (d) and migration rate (km/d) through Lower Granite Reservoir for PIT-tagged chinook salmon and steelhead trout, marked at the head of the reservoir were affected by discharge. For fish tagged at the Snake River trap, statistical analysis of 1998 detected a significant relation between migration rate and discharge. For hatchery and

  18. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 1990 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Nelson, V. Lance

    1991-05-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha and steelhead trout Oncorhynchus mvkiss smolts during the 1990 spring outmigration at migrant traps on the Snake River and the Clearwater River. Chinook salmon catch at the Snake River trap was similar to 1987 and 1988, drought years, but considerably less than 1989, a near normal flow year. Trapping effort was the same during the four years. Hatchery steelhead trout catch was similar to 1988 and 1989. Wild steelhead trout catch was greater than in any previous year. Chinook salmon catch at the Clearwater River trap was slightly less than in 1987 or 1988 and considerably higher than in 1989. Hatchery steelhead trout trap catch was 3 to 26 times greater than in previous years. Wild steelhead trout trap catch was 2 to 11 times greater than in previous years. Fish tagged with Passive Integrated Transponder (PIT) tags at the Snake River trap were recovered at the three dams with PIT tag detection systems (Lower Granite, Little Goose, and McNary dams). Cumulative recovery at the three dams for fish marked at the Snake River trap was 64.4% for chinook salmon, 83.1% for hatchery steelhead trout, and 79.0% for wild steelhead trout. Cumulative recovery at the three dams for fish PIT-tagged at the Clearwater River trap was 54.6% for chinook salmon, 77.6% for hatchery steelhead trout, and 70.4% for wild steelhead trout. Travel time (days) and migration rate (km/d) through Lower Granite Reservoir for PIT-tagged chinook salmon and steelhead trout, marked at the head of the reservoir, was affected by discharge. Statistical analysis showed that a two-fold increase in discharge increased migration rate by 2.2 times for PIT-tagged chinook salmon released from the Snake River trap and 1.8 times for chinook salmon released from the Clearwater River trap. A two-fold increase in discharge increased migration rate by 3.1 times for PIT-tagged hatchery steelhead trout released from the Snake River trap

  19. THE KIGOM PERALKALINE GRANITE PLUTON OF THE NIGERIAN ...

    African Journals Online (AJOL)

    The kigom granites in central Nigeria are alkali amphibole bearing and peralkaline in nature. They are hypersolvus in character and contain mesoperthite in which the albite (Or1-2) and microcline are present in approximately equal proportions. The albite is fully ordered while K-rich feldspar is dominantly microcline.

  20. Effects of Weathering on Mechanical Properties of Granite Gneiss ...

    African Journals Online (AJOL)

    This paper describes the geotechnical characteristics of granite gneiss and dolerite from Oban and Obuduregions in South-eastern Nigeria. The suitability of these rocks for civil construction purposes and the effects of weathering on their mechanical properties are examined. The results indicate that compressive strength ...

  1. Erosion over time on severely disturbed granitic soils: a model

    Science.gov (United States)

    W. F. Megahan

    1974-01-01

    A negative exponential equation containing three parameters was derived to describe time trends in surface erosion on severely disturbed soils. Data from four different studies of surface erosion on roads constructed from the granitic materials found in the Idaho Batholith were used to develop equation parameters. The evidence suggests that surface "armoring...

  2. Assessment of radioactivity in building material(granite) in Sudan

    International Nuclear Information System (INIS)

    Osman, Z. A; Salih, I; Albadwai, K. A; Salih, A. M; Salih, S. A.

    2016-01-01

    In the present work radioactivity in building materials (granite) central Sudan was evaluated. In general the building materials used in Sudan are derived either from rocks or soil. These contain trace amounts of naturally occurring radioactive materials(NORMs), so it contains radionuclides from uranium and thorium series and natural potassium. The levels of these radionuclides vary according to the geology of their site of origin. High levels increase the risk of radiation exposure in homes(especially exposure due to radon). Investigation of radioactivity in granite used of the building materials in Sudan is carried out, a total of 18 major samples of granite have been collected and measured using X- ray fluorescence system (30 mci). The activity concentrations have been determined for uranium ( 238 U), thorium ('2 32 Th) and potassium( 40 K) in each sample. The concentrations of uranium have been found to range from 14.81 Bq/kg to 24.572 Bq/kg, thorium between 10.02 Bq/kg and 10.020-84.79 Bq/kg and the potassium concentration varies between 13.33 Bq/kg to 82.13 Bq/kg. Limits of radioactivity in the granite are based on dose criteria for controls. This study can be used as a reference for more extensive studies of the same subject in future. (Author)

  3. lithologic features and uranium possibilities of the granites of pupule ...

    African Journals Online (AJOL)

    and interpretation of the result suggest that the fairly enhanced radioactivity in the fine-grained granite, southeast of. Pupule, may be related to ..... Elements distribution patterns in the uranium occurrence at Mika, Northeastern Nigeria. Chemie der Erde,. 56, 215-260. Geological Survey of Nigeria, (1974). Geological map of.

  4. fracture systems in the younger granite rocks around fobur, northern ...

    African Journals Online (AJOL)

    Admin

    Bowden, P. and Turner, D.C., 1974. Peralkaline and associated ring complexes in the Nigerian-Niger. Province, West Africa. In: The Alkaline Rocks,. H. Serensen (ed) John Willey, New York. pp.330-351. Bowden, P., Whitley, J.E. and Van Breeman, O., 1989. Geochemical studies on the Younger Granites of northern Nigeria.

  5. Fourier-transform Infrared Characterization of Kaolin, Granite ...

    African Journals Online (AJOL)

    Fourier-transform Infrared Characterization of Kaolin, Granite, Bentonite and Barite. ... Diazonium salts at the peak region frequency of 3200-3100cm-1, organic substance at peak region of 2900-2700cm-1, by comparing the spectra obtained with those ... Keywords: characterization; clays; infrared; minerals; spectroscopy ...

  6. Evolutionary trend of the Jarawa younger granites ring complex, Jos ...

    African Journals Online (AJOL)

    The Jarawa Younger Granites Ring Complex which occupies the eastern flank of the popular Jos-Bukuru Ring Complex in Central Nigeria was geologically and geochemically investigated in order to identify the different lithologic units that make up the formation, as well as understand its geochemistry. These were used to ...

  7. Geochemical trends in the weathered profiles above granite gneiss ...

    African Journals Online (AJOL)

    Geochemical trends in the weathered profiles above granite gneiss and schist of Abeokuta area, southwestern Nigeria. Anthony T Bolarinwa, Anthony A Elueze. Abstract. No Abstract. Journal of Mining and Geology 2005, Vol. 41(1): 19-31. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT ...

  8. Extraction of Th and U from Swiss granites

    International Nuclear Information System (INIS)

    Bajo, C.

    1980-12-01

    The extraction, at the laboratory level, of U and Th from Swiss granites is discussed. The Mittagfluh, Bergell and Rotondo granites and the Giuv syenite offered a wide range of U and Th concentrations; 7.7 to 20.0 ppm U and 25.5 to 67.0 ppm Th. U and Th were determined in the leach solutions by the fission track method and by spectrophotometry, respectively. Samples containing less than 0.3 μg U and 4 μg Th, could be measured with an accuracy of 10% for U and 5% for Th. Leach tests were performed during which the following parameters were varied: granite-type, grain size, acid-type, acid concentration, temperature and time. There were very great leaching differences between the granites studied. Temperature was the most important parameter. Sharp differences in extraction occurred between 20 0 C, 50 0 C and 80 0 C. At 80 0 C, more than 85% U and Th were extracted. The extraction curve (percent extracted as a function of time) of aliquots sampled after 1, 2, 4, 8, 12 and 24 hours showed a plateau after 8 hours. The half life of the reaction was between one and two hours. As a general rule, Th was better extracted than U. (Auth.)

  9. Characteristics of pegmatoidal granite exposed near Bayalan, Ajmer ...

    Indian Academy of Sciences (India)

    Introduction. A long geological history since Middle Archaean is recorded in ... Keywords. Pegmatoidal granite; Bhim Group; South Delhi Fold Belt; phacolith. J. Earth Syst. Sci. 120, No. 4, August 2011, pp. 617–626. cO Indian Academy of Sciences. 617 ... ates, epidote, sphene, apatite, zircon with rare occurrences of zoisite ...

  10. Water–rock interaction on the development of granite gneissic ...

    Indian Academy of Sciences (India)

    Water–rock interaction on the development of granite gneissic weathered profiles in Garhwal Lesser Himalaya, India. S Vyshnavi and R Islam∗. Wadia Institute of Himalayan Geology, Dehradun 248 001, India. ∗Corresponding author. e-mail: rislam@wihg.res.in. The development and sustainability of weathered profiles are ...

  11. Tectonic imprints within a granite exposed near Srinagar, Rajasthan ...

    Indian Academy of Sciences (India)

    schists, argillites, and quartzite. He did not men- tion the occurrence of any granite from the area. The presence of thick conglomerate along the east- ern margin is a rare feature in the DFB rocks unlike the western margin of DFB, where Heron (1953),. Murthy and Bhargava (1972), Biswal (1993) and. Dasgupta et al. (2012) ...

  12. Fracture systems in the younger granite rocks around fobur, northern ...

    African Journals Online (AJOL)

    Outcrop-scale fractures and associated veins found in the Younger Granite rocks around Fobur, Northern Nigeria were studied in relation to similar structures in their host rocks (Migmatites-gneisses -quartzite complex). Fractures and veins attitude (strike and dip) data were collected across the study area and subjected to ...

  13. Aggregate impact testing of selected granite samples from sites in ...

    African Journals Online (AJOL)

    The Aggregate Impact Testing machine was used to measure the resistance to fa ilure of Rocks from five (5) selected granite quarries to a suddenly applied force using S ingapore standard. The results obtained show that brittleness (S20) value of the rocks were between 2 - 10. These values are less than the stated ...

  14. Characteristics of pegmatoidal granite exposed near Bayalan, Ajmer ...

    Indian Academy of Sciences (India)

    Roy 1984; Gupta and Bose 2000). The aim of the present study is to elucidate the tectonic evolu- ... on the hinges of the folds defined by the gneissosity. Keywords. Pegmatoidal granite; Bhim Group; South Delhi Fold Belt; phacolith. J. Earth Syst. Sci. 120, No. 4, August 2011, pp. 617–626. cO Indian Academy of Sciences.

  15. Coastal Inlet Model Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Coastal Inlet Model Facility, as part of the Coastal Inlets Research Program (CIRP), is an idealized inlet dedicated to the study of coastal inlets and equipped...

  16. Etude de la diagraphie neutron du granite de Beauvoir. Effet neutron des altérations et de la matrice du granite. Calibration granite. Porosité totale à l'eau et porosité neutron Analysis of the Beauvoir Granite Neutron Log. Neutron Effect of Alterations and of the Granite Matrix. Granite Calibration. Total Water Porosity and Neutron Porosity

    Directory of Open Access Journals (Sweden)

    Galle C.

    2006-11-01

    Full Text Available Cet article rend compte des travaux effectués sur la porosité du granite de Beauvoir (Sondage GPF 1 d'Echassières, Massif Central français. L'objectif de notre étude est de pouvoir obtenir des valeurs représentatives de la saturation en eau (porosité totale à l'eau n du granite de Beauvoir à partir des mesures de porosité neutron PorositéN (diagraphie neutron BRGM sans avoir recours aux mesures sur carottes. Notre démarche est expérimentale et nous avons tenté d'approfondir certains problèmes liés à l'utilisation de la diagraphie neutron dans une roche granitique. Deux facteurs principaux conditionnent la réponse neutron : la concentration en hydrogène de la formation (eau libre et eau de constitution de certains minéraux et la présence d'éléments absorbeurs à forte section de capture comme le gadolinium, le cadmium, le bore, . . . et dans le cas du granite de Beauvoir, le lithium. A partir des mesures de porosité totale à l'eau n sur carottes, des essais de pertes au feu sur poudre qui nous permettent de déterminer la porosité neutron liée à l'eau de constitution PorositéN(OH- et des analyses chimiques avec lesquelles nous évaluons la porosité neutron thermique PorositéN(ox (Programme SNUPAR, Schlumberger liée à la capture neutronique, nous reconstituons la porosité neutron totale PorositéNR du granite de Beauvoir. Pour 7 échantillons caractéristiques du granite de Beauvoir, nous réalisons grâce à ces résultats une nouvelle calibration du taux de comptage neutron initial corrigé du gradient thermique et de l'effet de trou. Grâce à cette opération, il est possible de déterminer, pour les échantillons traités, la porosité neutron du granite avec une calibration granite (PorositéNg et non calcaire (PorositéNc. La connaissance de l'effet neutron de la matrice nous permet enfin d'évaluer la teneur en eau du granite (porosité totale à l'eau et de comparer celle-ci avec la porosité mesurée sur

  17. Petrogenesis of the Late Jurassic peraluminous biotite granites and muscovite-bearing granites in SE China: geochronological, elemental and Sr-Nd-O-Hf isotopic constraints

    Science.gov (United States)

    Jiang, Yao-Hui; Zhu, Shu-Qi

    2017-12-01

    Biotite granites and muscovite-bearing granites are dominant rock types of the widespread granites in SE China. However, their petrogenesis has been enigmatic. A combined study of zircon U-Pb dating and Lu-Hf isotopes, whole-rock element geochemistry and Sr-Nd-O isotopes was performed for three late Mesozoic granitic plutons (Xinfengjie, Jiangbei and Dabu) in central Jiangxi province, SE China. All the plutons are composed of biotite granites and muscovite-bearing granites that have been poorly investigated previously. The new data not only allow us to assess their sources and magma evolution processes, but also helps us to better understand the genetic link to the large-scale polymetallic mineralization in SE China. LA-ICP-MS zircon U-Pb dating shows that three plutons were emplaced in the Late Jurassic (159-148 Ma) and that the muscovite-bearing granites are almost contemporaneous with the biotite granites. The biotite granites have SiO2 contents of 70.3-74.4 wt% and are weakly to strongly peraluminous with ASI from 1.00 to 1.26, and show a general decrease in ASI with increasing SiO2. They have relatively high zircon saturation temperatures ( T Zr = 707-817 °C, most > 745 °C) and show a general decrease in T Zr with increasing SiO2. They have high initial 87Sr/86Sr ratios (0.7136 to 0.7166) and high δ18O values (9.1-12.8‰, most > 9.5‰) and clearly negative ɛ Nd (T) (- 9.5 to - 11.8) and ɛ Hf (T) (in situ zircon) (- 13.1 to - 13.5). The muscovite-bearing granites have high SiO2 contents (74.7-78.2 wt%). They are also weakly to strongly peraluminous with ASI of 1.04-1.18 but show a general increase in ASI with increasing SiO2. They have relatively low T Zr (671-764 °C, most 9.5‰) and ɛ Hf (T) (in situ zircon) of - 11.3 to - 13.1. Geochemical data suggest the origin of the biotite granites and muscovite-bearing granites as follows: Partial melting of Precambrian metasedimentary rocks (mainly two-mica schist) in the lower crust at temperatures of ca

  18. Introduction to coastal engineering

    NARCIS (Netherlands)

    D' Angremond, K.; Pluim-van der Velden, E.T.J.M.

    Lecture notes on genesis of the coastline, climatology, oceanography, coastal morphology, coastal formations, coastalzonde management, tidal inlets and estuaries, pollution and density problems, practical problems and common solutions.

  19. The transition from granite to banded aplite-pegmatite sheet complexes: An example from Megiliggar Rocks, Tregonning topaz granite, Cornwall

    Czech Academy of Sciences Publication Activity Database

    Breiter, Karel; Ďurišová, Jana; Hrstka, Tomáš; Korbelová, Zuzana; Vašinová Galiová, M.; Müller, A.; Simons, B.; Shail, R. K.; Williamson, B. J.; Davies, J. A.

    302/303, March 2018 (2018), s. 370-388 ISSN 0024-4937 R&D Projects: GA ČR GA14-13600S Institutional support: RVO:67985831 Keywords : granite * aplite * pegmatite * magmatic layering * Megiliggar Rocks * Cornwall Subject RIV: DB - Geology ; Mineralogy OBOR OECD: Geology Impact factor: 3.677, year: 2016

  20. Zarzalejo granite (Spain). A nomination for 'Global Heritage Stone Resource'

    Science.gov (United States)

    Freire Lista, David Martin; Fort, Rafael; José Varas-Muriel, María

    2015-04-01

    Zarzalejo granite is quarried in the Sierra de Guadarrama (Spanish Central System) foothills, in and around Zarzalejo village, in the province of Madrid, Spain. It is an inequigranular monzogranite medium-to-coarse grained, with a slight porphyritic texture (feldspar phenocrysts) and mafic micro-grained enclaves. In this abstract the candidacy of Zarzalejo granite as a "Global Heritage Resource Stone" (GHSR) is presented. This stone ideally fits the newly proposed designation as it has been used in many heritage buildings and its good petrophysical properties and durability have allowed well preserved constructions such as a Roman road, San Pedro Church in Zarzalejo (1492), Descalzas Reales Monastery in Madrid (1559-1564) and the San Lorenzo del Escorial Royal Monastery (1563-1584), to be declared a World Heritage Site by UNESCO. This level of construction has been a landmark in the extraction and proliferation of historic quarries created due to the high demand that such colossal monuments and buildings with granite, have required for their construction. In the mid-20th century, More, Zarzalejo granite has also been used in restoration works including the Royal Palace and the Reina Sofía Museum (2001-2005), both buildings in Madrid, Spain. Extraction of granite ashlars from tors has been a very frequent activity in the Zarzalejo neighbourhood until mid-twentieth century. So there is also a need to preserve these historic quarries. This type of stone has created a landscape that has been preserved as an open-air museum today where you can see the marks left in the granite due to historic quarry operations. The granite industry has been one of the main pillars of the Zarzalejo regional economy. For centuries, the local community have been engaged in quarrying and have created a cultural landscape based on its building stone. A quarryman monument has been erected in Zarzalejo in honor of this traditional craft as well as an architecture museum at San Lorenzo del

  1. A-type granite and the Red Sea opening

    Science.gov (United States)

    Coleman, R.G.; DeBari, S.; Peterman, Z.

    1992-01-01

    Miocene-Oligocene A-type granite intrudes the eastern side of the Red Sea margin within the zone of extension from Jiddah, Saudi Arabia south to Yemen. The intrusions developed in the early stages of continental extension as Arabia began to move slowly away from Africa (around 30-20 Ma). Within the narrow zone of extension silicic magmas formed dikes, sills, small plutons and extrusive equivalents. In the Jabal Tirf area of Saudi Arabia these rocks occur in an elongate zone consisting of late Precambrian basement to the east, which is gradually invaded by mafic dikes. The number of dikes increases westward until an igneous complex is produced parallel to the present Red Sea axis. The Jabal Tirf igneous complex consists of diabase and rhyolite-granophyre sills (20-24 Ma). Although these are intrusine intrusive rocks their textures indicate shallow depths of intrusion (Yemen, contemporaneous with alkali basaltic eruptions (26-30 Ma) and later silicic eruptions, small plutons, dikes, and stocks of alkali granite invaded thick (1500 m) volcanic series, at various levels and times. Erosion within the uplifted margin of Yemen suggests that the maximum depth of intrusion was less than 1-2 km. Granophyric intrusions (20-30 Ma) within mafic dike swarms similar to the Jabal Tirf complex are present along the western edge of the Yemen volcanic plateau, marking a north-south zone of continental extension. The alkali granites of Yemen consist primarily of perthitic feldspar and quartz with some minor alkali amphiboles and acmite. These granites represent water-poor, hypersolvus magmas generated from parent alkali basalt magmas. The granophyric, two-feldspar granites associated with the mafic dike swarms and layered gabbros formed by fractional crystallization from tholeiitic basalt parent developed in the early stages of extension. Initial 87Sr/86Sr ratios of these rocks and their bulk chemistry indicate that production of peralkaline and metaluminous granitic magmas involved

  2. Alteration of granite stone used in building construction

    Directory of Open Access Journals (Sweden)

    Esbert Alemany, R. M.ª

    2007-12-01

    Full Text Available The article contains a synthesis of the different factors involved in the alteration of granite ashlars or cladding used in building construction. Emphasis is placed on the – primarily fissure-like – anisotropies often present in granite, which are usually related to the structural conditions of the quarry where it is mined. Such anisotropies condition the development of certain types of alterations that appear over time, particularly in ashlars. Stone petrography, particularly as regards the chemical composition of the minerals comprising granite, also govern its alteration. Moreover, the commercial term granite often includes other more alkaline rocks generically known as granitoids, whose alterability is higher than in granite per se. The values of some of the physical properties of these rocks, which must be quantified to evaluate their durability, are shown to differ in keeping with their anisotropy. Finally, the forms, causes and mechanisms involved in granite decay are reviewed in the context of its use in building construction.En el artículo se sintetizan los diversos aspectos que inciden en la alteración de las rocas graníticas, cuando estas se utilizan en los edificios, ya sea en forma de sillares o de losetas de revestimiento. Se hace especial hincapié en las anisotropías, fundamentalmente de carácter fisural que suelen presentar los granitos. Estas suelen estar relacionadas con las condiciones estructurales del yacimiento del cual proceden. Dichas anisotropías condicionan el desarrollo de determinadas formas de alteración que con el paso del tiempo se aprecian, sobre todo en los sillares. También se recuerda que la petrografía, y en especial la composición química de los minerales que componen las rocas graníticas, condicionan su alteración, y que dentro del término comercial granito se suelen incluir otras rocas más alcalinas denominadas genéricamente granitoides y más alterables que el granito sensu

  3. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 1997 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Nelson, William R.

    1999-04-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha and steelhead trout O. mykiss smolts during the 1997 spring out-migration at migrant traps on the Snake River and Salmon River. All hatchery chinook salmon released above Lower Granite Dam were marked with a fin clip in 1997. Total annual hatchery chinook salmon catch at the Snake River trap was 49% of the 1996 number but only 6% of the 1995 catch. The wild chinook catch was 77% of the 1996 but was only 13% of 1995. Hatchery steelhead trout catch was 18% of 1996 numbers but only 7% of the 1995 numbers. Wild steelhead trout catch was 22% of 1996 but only 11% of the 1995 numbers. The Snake River trap collected eight age-0 chinook salmon and one sockeye/kokanee salmon O. nerka. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with high flows. Trap operations were terminated for the season due to high flows and trap damage on May 8 and were out of operation for 23 d due to high flow and debris. Hatchery chinook salmon catch at the Salmon River trap was 37% and wild chinook salmon catch was 60% of 1996 numbers but only 5% and 11% of 1995 catch, respectively. The 1997 hatchery steelhead trout collection was 13% of the 1996 catch and 32% of the 1995 numbers. Wild steelhead trout collection in 1997 was 21% of the 1996 catch and 13% of the 1995 numbers. Trap operations were terminated for the season due to high flows and trap damage on May 7 and were out of operation for 19 d due to high flow and debris.

  4. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Brimmer, Arnold F.; Putnam, Scott A.

    2001-06-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon smolts O. nerka during the 1999 spring out-migration at migrant traps on the Snake River and Salmon River. All hatchery chinook salmon released above Lower Granite Dam were marked with a fin clip in 1999. Total annual hatchery chinook salmon catch at the Snake River trap was 440% of the 1998 number. The wild chinook catch was 603% of the previous year's catch. Hatchery steelhead trout catch was 93% of 1998 numbers. Wild steelhead trout catch was 68% of 1998 numbers. The Snake River trap collected 62 age-0 chinook salmon. During 1998 the Snake River trap captured 173 hatchery and 37 wild/natural sockeye salmon and 130 hatchery coho salmon O. kisutch. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with high flows. Trap operations began on March 14 and were terminated for the season due to high flows on May 25. The trap was out of operation for 18 d during the season due to high flow and debris. Hatchery chinook salmon catch at the Salmon River trap was 214%, and wild chinook salmon catch was 384% of 1998 numbers. The hatchery steelhead trout collection in 1999 was 210% of the 1998 numbers. Wild steelhead trout collection in 1999 was 203% of the 1998 catch. Trap operations began on March 14 and were terminated for the season due to high flows on May 21. The trap was out of operation for 17 d during the season due to high flow and debris.

  5. Failure of Sierra White granite under general states of stress

    Science.gov (United States)

    Ingraham, M. D.; Dewers, T. A.; Lee, M.; Holdman, O.; Cheung, C.; Haimson, B. C.

    2017-12-01

    The effect of the intermediate principal stress on the failure of Sierra White granite was investigated by performing tests under true triaxial states of stress. Tests were performed under constant Lode angle conditions with Lode angles ranging from 0 to 30°, pure shear to axisymmetric compression. Results show that the failure of Sierra White granite is heavily dependent on the intermediate principal stress which became more dramatic as the mean stress increased. An analysis of the shear bands formed at failure was performed using an associated flow rule and the Rudnicki and Rice (1975) localization criteria. The localization analysis showed excellent agreement with experimental results. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA0003525.

  6. Quantized Ultracold Neutrons in Rough Waveguides: GRANIT Experiments and Beyond

    Directory of Open Access Journals (Sweden)

    M. Escobar

    2014-01-01

    Full Text Available We apply our general theory of transport in systems with random rough boundaries to gravitationally quantized ultracold neutrons in rough waveguides as in GRANIT experiments (ILL, Grenoble. We consider waveguides with roughness in both two and one dimensions (2D and 1D. In the biased diffusion approximation the depletion times for the gravitational quantum states can be easily expressed via each other irrespective of the system parameters. The calculation of the exit neutron count reduces to evaluation of a single constant which contains a complicated integral of the correlation function of surface roughness. In the case of 1D roughness (random grating this constant is calculated analytically for common types of the correlation functions. The results obey simple scaling relations which are slightly different in 1D and 2D. We predict the exit neutron count for the new GRANIT cell.

  7. Radon exhalation rates of some granites used in Serbia

    Directory of Open Access Journals (Sweden)

    Nikolić Mladen D.

    2015-01-01

    Full Text Available In order to address concern about radon exhalation in building material, radon exhalation rate was determined for different granites available on Serbian market. Radon exhalation rate, along with mass exhalation rate and effective radium content were determined by closed chamber method and active continuous radon measurement technique. For this research, special chambers were made and tested for back diffusion and leakage, and the radon concentrations measured were included in the calculation of radon exhalation. The radon exhalation rate ranged from 0.161 Bq/m2h to 0.576 Bq/m2h, the mass exhalation rate from 0.167 Bq/kgh to 0.678 Bq/kgh, while the effective radium content was found to be from 12.37 Bq/kg to 50.23 Bq/kg. The results indicate that the granites used in Serbia have a low level of radon exhalation.

  8. 1997 Lower Granite dam smolt monitoring program : annual report.; ANNUAL

    International Nuclear Information System (INIS)

    Morrill, Charles; Ross, Doug; Verhey, Peter; Witalis, Shirley

    1997-01-01

    The 1997 fish collection season at Lower Granite was characterized by high spring flows, extensive spill, cool spring and early summer water temperatures and comparatively low numbers of fish, particularly yearling chinook. The Fish Passage Center's Smolt Monitoring Program is designed to provide a consistent, real-time database of fish passage and document the migrational characteristics of the many stocks of salmon and steelhead in the Columbia Basin

  9. Static and kinetic friction of granite at high normal stress

    Science.gov (United States)

    Byerlee, J.D.

    1970-01-01

    Frictional sliding on ground surfaces of granite, angle of sliding planes 30?? and 45??, was investigated as a function of confining pressure. Over the normal stress range of 2-12 kb, the static frictional shear stress ??s follows the relationship ??s = 0??5 + 0?? ??n and the kinetic frictional shear stress ??k was calculated to be ??k = 0??25 + 0??47 ??n. ?? 1970.

  10. Heat transfer experiment in a granite formation at Cornwall

    International Nuclear Information System (INIS)

    Bourke, P.J.; Hodgkinson, D.P.

    1985-01-01

    An experiment simulating a waste package was started in 1978 in Cornish granite. To obtain measurable temperature rises through large volumes of rock, an electrical heater at 50m depth was run for four years. The heater was then switched off and the cooling was monitored for another year. The results show that most of the heat transfer was by conduction but that some convection occurred and that temperatures can be predicted with some confidence

  11. High radiocesium levels in granite outcrop vegetation and reductions through time

    International Nuclear Information System (INIS)

    Garner, J.A.; Jenkins, J.H.

    1991-01-01

    Levels of fallout radiocesium in vegetation were examined on three granite outcrops and a forested area in the Georgia piedmont during 1976-1980. Mean values averaged 4.3 times higher in three species collected on an outcrop than in the same species collected on clay soils in a nearby pine-hardwood forest. Levels in reindeer moss (Cladonia spp.) were significantly (p less than 0.01) lower in species that formed deep, entangled tufts with abundant, slender branches. Cesium levels decreased by as much as 90% from the mid-1960s but were virtually unchanged in the late 1970s. Dry-weight levels in mushrooms reached 18,470 Bq kg-1 (499.2 pCi g-1). Radiation levels in outcrop vegetation were higher than values found anywhere in the piedmont and were comparable to levels reported in plants from the sterile sandy soils of the temperate region coastal plains. These data fit well with earlier reported values and correlate well with the availability of atmospheric fallout. Outcrops can be used as sensitive environmental barometers for some contaminants

  12. Lower Granite dam smolt monitoring program: annual report, 2000; ANNUAL

    International Nuclear Information System (INIS)

    Morrill, Charles

    2000-01-01

    The 2000 fish collection season at Lower Granite was characterized by lower than average spring flows and spill, low levels of debris, cool water temperatures, increased unclipped yearling and subyearling chinook smolts, and 8,300,546 smolts collected and transported compared to 5,882,872 in 1999. With the continued release of unclipped supplementation chinook and steelhead above Lower Granite Dam, we can no longer accurately distinguish wild chinook, steelhead, and sockeye/kokanee in the sample. Although some table titles in this report still show ''wild'' column headings, the numbers in these columns for 1999 and 2000 include wild and unclipped hatchery origin smolts. The increases over previous years reflect the increased supplementation. A total of 8,300,546 juvenile salmonids were collected at Lower Granite Dam. Of these, 187,862 fish were bypassed back to the river and 7,950,648 were transported to release sites below Bonneville Dam, 7,778,853 by barge and 171,795 by truck. A total of 151,344 salmonids were examined in daily samples. Nine research projects conducted by four agencies impacted a total of 1,361,006 smolts (16.4% of the total collection)

  13. Study of natural radioactivity in Mansehra granite, Pakistan: environmental concerns

    International Nuclear Information System (INIS)

    Qureshi, Aziz Ahmed; Manzoor, Shahid; Waheed, Abdul; Tubassam, Aneela; Khan Jadoon, Ishtiaq Ahmed; Wajid, Ali Abbas; Attique, Ahsan; Masood, Adil; Anees, Muhammad

    2014-01-01

    A part of Mansehra Granite was selected for the assessment of radiological hazards. The average activity concentrations of 226 Ra, 232 Th and 40 K were found to be 27.32, 50.07 and 953.10 Bq kg -1 , respectively. These values are in the median range when compared with the granites around the world. Radiological hazard indices and annual effective doses were estimated. All of these indices were found to be within the criterion limits except outdoor external dose (82.38 nGy h -1 ) and indoor external dose (156.04 nGy h -1 ), which are higher than the world's average background levels of 51 and 55 nGy h -1 , respectively. These values correspond to an average annual effective dose of 0.867 mSv y -1 , which is less than the criterion limit of 1 mSv y -1 (ICRP-103). Some localities in the Mansehra city have annual effective dose higher than the limit of 1 mSv y -1 . Overall, the Mansehra Granite does not pose any significant radiological health hazard in the outdoor or indoor. (authors)

  14. Geochronology and geochemistry of upper proterozoic granites from Southern Benin

    International Nuclear Information System (INIS)

    Cordani, U.G.; Kawashita, K.; Vancini, K.R.B.; Cadoppi, P.; Sacchi, R.

    1993-01-01

    The Upper Proterozoic basement of Benin, like that of nearby Nigeria and like the polycyclic basement of Central Hoggar, belongs to the hinterland of the Pharusian Chain (Pan-African Trans-Saharan Belt) generated by the collision between the (passive) margin of the West African craton and the (reactivated) margin of the Tuareg Shield and its southern extension. Rb-Sr dating of sub alkaline, meta-aluminums, syn-Kinematic granite forming tabular bodies near Dassa-Zoume and near Save yielded two WR isochron ages of 650 ± 35 Ma (I.R. = 0.7043) and 705 ± 70 Ma (I.R. = 0.7045). Emplacement of these bodies was clearly controlled by trans current movements along the Kandi Fault System. The analyzed granites are comparable with those of Central Hoggar and North-Central Nigeria on the ground of field, geochronological and geochemical data; they also display some affinities with the late-tectonic granites of the Adrar des Iforas. They are expected to find their Brazilian continuation in the Chaval Granitoids west of Fortaleza, but data for comparison are inadequate. (author)

  15. Permian ultrafelsic A-type granite from Besar Islands group, Johor, peninsular Malaysia

    Science.gov (United States)

    Ghani, Azman A.; Hazad, Fatin Izzani; Jamil, Azmiah; Xiang, Quek Long; Atiqah Wan Ismail, Wan Nur; Chung, Sun-Lin; Lai, Yu-Ming; Roselee, Muhammad Hatta; Islami, Nur; Nyein, Kyaw Kyaw; Amir Hassan, Meor Hakif; Abu Bakar, Mohd Farid; Umor, Mohd Rozi

    2014-12-01

    The granitic rocks of the peninsula have traditionally been divided into two provinces, i.e., Western and Eastern provinces, corresponding to S- and I-type granite respectively. The Western Province granite is characterised by megacrystic and coarse-grained biotite, tin-mineralised, continental collision granite, whereas, the Eastern Province granite is bimodal I-type dominated by granodiorite and associated gabbroic of arc type granite. This paper reports the occurrence of an A-type granite from peninsular Malaysia. The rocks occur in the Besar, Tengah, and Hujung islands located in the southeastern part of the peninsula. The granite is highly felsic with SiO2 ranging from 75.70% to 77.90% (differentiation index = 94.2-97.04). It is weakly peraluminous (average ACNK =1.02), has normative hypersthene (0.09-2.19%) and high alkali content (8.32-8.60%). The granites have many A-type characteristics, among them are shallow level of emplacement, high Ga, FeT/MgO and low P, Sr, Ti, CaO and Nb. Calculated zircon saturation temperatures for the Besar magma ranging from 793 ∘ to 806 ∘C is consistent with high temperature partial melting of a felsic infracrustal source which is taken as one of the mechanisms to produce A-type magma. The occurrence of the A-type granite can be related to the extensional back arc basin in the Indo-China terrane during the earliest Permian.

  16. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam, 1992 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Brimmer, Arnold F.

    1993-11-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha and steelhead trout 0. mykiss smolts during the 1992 spring outmigration at migrant traps on the Snake River and the Clearwater River. Annual chinook salmon catch at the Snake River trap was the second lowest since the beginning of this project. The low trap catch wall due to extremely poor trap efficiency associated with severe low flows. Hatchery steelhead trout catch was similar to 1988 through 1991. Wild steelhead trout catch was 35% less than in 1991. Operations at the Snake River trap and a new screw trap were extended through the end of July to collect summer-migrating age-0 chinook. The differentiation of age-0 chinook from spring and Bummer chinook (age-1) using physical characteristics was again employed in 1992. The Snake River trap and the screw trap collected 20 and 18 age-0 chinook salmon, respectively, due to extremely low discharge. Chinook salmon catch at the Clearwater River trap was the highest since trap operation began in 1984. Hatchery steelhead trout trap catch was 23% lower than in 1991. Wild steelhead trout trap catch wall the highest since trap operation began. Fish tagged with Passive Integrated Transponder (PIT) tags at the Snake River trap were interrogated at three dams with PIT-tag detection systems (Lower Granite, Little Goose, and McNary dams). Cumulative interrogation, for fish marked at the Snake River trap, was not calculated for chinook salmon due to a lack of data over the entire migration season. The rates for hatchery steelhead trout and wild steelhead trout were 44.9% and 72.9% respectively. Cumulative interrogation at the three dams for fish PIT-tagged at the Clearwater River trap was 55.1% for chinook salmon, 60.4% for hatchery steelhead trout, and 73.1% for wild steelhead trout. Cumulative interrogations for hatchery steelhead tagged at the Snake River trap and recovered at the downstream dams was about 50% less than in previous years.

  17. Petrography and geochemistry of the topaz-bearing granite stocks in Artjärvi and Sääskjärvi, western margin of the Wiborg rapakivi granite batholith

    Directory of Open Access Journals (Sweden)

    Sari Lukkari

    2002-01-01

    Full Text Available The Artjärvi and Sääskjärvi granite stocks at the western margin of the Wiborg rapakivi batholith are multiphase rapakivi granite intrusions in which the most evolved phase is topaz-bearing granite. The Artjärvi stock is composed of porphyritic and even-grained biotite granite and even-grained topaz granite, and the Sääskjärvi stock comprises even-grained biotite granite and porphyritic topazgranite. The granites are metaluminous to peraluminous A-type granites, showing within-plate (WPG geochemical characteristics. The topaz granites from the Artjärvi and Sääskjärvi stocks are petrographically and geochemically similar to other topaz-bearing rapakivi granites in Finland. The anomalous geochemistry of the topaz granite is essentially magmatic; postmagmatic reactions have only slightly modified its composition. Greisen veins, some of which are mineralized, are widely found associated with the Artjärvi and Sääskjärvi stocks.The most characteristic feature of the Artjärvi granite stock is a stockscheider at the roof contact of the topaz granite. The stockscheider is composed of schlieren layering and pegmatite layers parallel to the contact. The most probable mechanism for the formation of the schlieren layering is velocity-gradient sorting parallel to the flow, which led to accumulation of mafic minerals along the upper contact of the topaz granite. Cooling and contraction of the topaz granite formed fractures parallel to the roof contact and the residual pegmatite magmas were injected along the fractures forming pegmatite layers. Textures like graphic intergrowths, aplitic groundmass and fan-shaped alkali feldspar crystals associated with the Artjärvi porphyritic biotite granite and pegmatite indicatecrystallization from undercooled magma. Miarolitic cavities found in the porphyritic biotite granite and topaz granite indicate at least local volatile saturation.

  18. Critical element ratio maps of granitic terrains for exploration of atomic minerals

    International Nuclear Information System (INIS)

    Viswanathan, S.; Singh, Yamuna

    2010-01-01

    The paper proposes a new type of geochemical map, named the 'Critical Element Ratio Map', involving K/Rb, Ba/Rb, and Rb/Sr ratios, to aid exploration programmes for atomic minerals in granitic terrains. Granitic rocks formed from highly evolved melts are favourable for hosting ore deposits of U, Th, Li, Be, Nb, Ta, Y, the rare-earth elements (REEs), Sn, W, and Cs. The characteristic geochemical features of this type of granite are low K/Rb and Ba/Rb ratios and high Rb/Sr ratios. The average K/Rb, Ba/Rb, and Rb/Sr ratios of high-calcium granitic rocks (tonalites, granodiorites, and leucogranodiorites) are 229, 8.18, and 0.25, and those for low-calcium granitic rocks (adamellites, granites, leucogranites, and alaskites) are 247, 2.35, and 1.70, respectively. In sharp contrast, the K/Rb, Ba/Rb, and Rb/Sr ratios of granitic rocks formed from highly evolved melts will be less than 100, less than 0.25, and more than 5, respectively. The paper also describes a simple, accurate, precise, rapid, and non-destructive method for determining K, Rb, Sr, and in granitic rocks by wavelength-dispersive X-ray fluorescence spectrometry (WDXRFS) and outlines the methodology for preparing 'Critical Element Ratio Maps' of granitic terrains. granite-hosted 'Rossing-Type' of uranium ore deposits are to be discovered in India, it will be possible only by launching an intensive programme for preparing 'Critical Element Ratio Maps' to identify granitic bodies characterized anomalously low K/Rb and Ba/Rb ratios and high Rb/Sr ratios within the large granitic terrains of Peninsular and Extra-Peninsular India. (author)

  19. New data on the age and nature of the Khan-Bogd alkaline granites, Mongolia

    Science.gov (United States)

    Gerdes, A.; Kogarko, L. N.; Vladykin, N. V.

    2017-11-01

    New age dating (291 Ma) was obtained for one of the largest alkaline granite massifs in the world, the Khan-Bogd Massif (Mongolia). For the first time, apart from zircon, other zirconium silicates, elpidite and armstrongite, have been analyzed. Our determinations showed the highly depleted nature of the mantle sources of granites with ɛNd = 12. All the studied Zr-silicates demonstrate positive Eu anomalies in the REE patterns, which indicate a low oxidation potential during alkaline granite formation.

  20. COASTAL CHARACTERISTICS OF SOUTH SINGKEP AREA, RIAU ISLANDS PROVINCE

    Directory of Open Access Journals (Sweden)

    Noor C.D. Aryanto

    2017-07-01

    Full Text Available Observations of coastal characteristics, such as coastal constituent lithology, oceanographic processes and the influence of human activities along the coastal area, are the factors that affect the coastal typology. The typology of coastal area can be divided into 3 types namely: (1 Sandy beaches, dominated by medium size quartz sand, gravelly sand and silt of alluvium deposits ; (2 Rocky beaches that belong to the Tanjung Buku Granite lithologic units and Persing metamorphic complex, its beach slope between 5° and 15°, and a fault structure encountered. The steep beach slopes (45°-50° trends to offshore with the maximum depth of 28 meters below the sea level at the distance of 3.5 km from the its shore line. At the depth of 20 m, there are a foot slope of 1.5 km width interpreted as the fault plane; (3 Muddy beaches is characterized by mangroves, gentle beach slopes until flats. Those sandy and muddy beaches are alluvial deposits of Quarternary sediments.

  1. Rare earths elements in the rocks of the Cinovec granite cupola (Czechoslovakia)

    International Nuclear Information System (INIS)

    Stemprok, M.

    1989-01-01

    Rare earth elements (REE) were analyzed by the nondestructive INAA method in samples from drilling CS-1 situated in the center of the Cinovec granite cupola, eastern Krusne hory Mts., Czechoslovakia. The 1596 m deep drilling found upper zinnwaldite and lower protolithionite granites which differ in their amounts of REE. Both types of granites that belong to the granites of the Younger Intrusive Complex of the Krusne Hory Mts. give flat chondrite-normalized patterns characterized by a large negative Eu anomaly. (author). 9 figs., 5 tabs., 25 refs

  2. Magmatic and crustal differentiation history of granitic rocks from Hf-O isotopes in zircon.

    Science.gov (United States)

    Kemp, A I S; Hawkesworth, C J; Foster, G L; Paterson, B A; Woodhead, J D; Hergt, J M; Gray, C M; Whitehouse, M J

    2007-02-16

    Granitic plutonism is the principal agent of crustal differentiation, but linking granite emplacement to crust formation requires knowledge of the magmatic evolution, which is notoriously difficult to reconstruct from bulk rock compositions. We unlocked the plutonic archive through hafnium (Hf) and oxygen (O) isotope analysis of zoned zircon crystals from the classic hornblende-bearing (I-type) granites of eastern Australia. This granite type forms by the reworking of sedimentary materials by mantle-like magmas instead of by remelting ancient metamorphosed igneous rocks as widely believed. I-type magmatism thus drives the coupled growth and differentiation of continental crust.

  3. The rapakivi granite plutons of Bodom and Obbnäs, southern Finland: petrography and geochemistry

    Directory of Open Access Journals (Sweden)

    Kosunen, P.

    1999-12-01

    Full Text Available The Obbnäs and Bodom granite plutons of southernmost Finland show the typical petrographic and geochemical features of the Proterozoic rapakivi granites in Finland and elsewhere: they cut sharply across the 1900 Ma Svecofennian metamorphic bedrock and have the geochemical characteristics of subalkaline A-type granites. The Bodom pluton is composed of porphyritic granites (hornblende-, hornblende-biotite-, and biotite-bearing varieties and an even-grained granite that probably represent two separate intrusive phases. This lithologic variation does not occur in the Obbnäs pluton, which is almost entirely composed of porphyritic hornblende-biotite granite that gradually becomes more mafic to the southwest. Three types of hybrid granitoids resulting from magma mingling and mixing occur on the southwestern tip of the Obbnäs peninsula. The Bodom granites are syenogranites, whereas the composition of the Obbnäs granite varies from syeno- to monzogranite. The main silicates of both the Bodom and Obbnäs granites are quartz, microcline, plagioclase (An1541, biotite (siderophyllite, and generally also amphibole (ferropargasite or hastingsite. Plagioclase-mantled alkali feldspar megacrysts are absent or rare. The accessory minerals are fluorite, allanite, zircon, apatite, and iron-titanium oxides; the Obbnäs granite also contains titanite. The Bodom and Obbnäs granites are metaluminous to weakly peraluminous, with average A/CNK of 1.00 and 1.05, respectively, have high Fe/Mg (average FeOtot/[FeOtot+MgO] is 0.94 for the Bodom and 0.87 for the Obbnäs granites, and high Ga/Al (3.78 to 5.22 in Bodom and 2.46 to 4.18 in Obbnäs. The REE contents are high with LREE-enriched chondrite-normalized patterns and moderate (Obbnäs to relatively strong (Bodom negative Eu-anomalies. The Obbnäs granite is enriched in CaO, TiO2, MgO, and FeO, and depleted in SiO2 and K2O compared to the Bodom granites. Also, there are differences in the Ba, Rb, and Sr contents of

  4. Evolution of zircons from postorogenic intrusive series with Li-F granites, Russian Far East

    Science.gov (United States)

    Alekseev, V. I.; Polyakova, E. V.; Machevariani, M. M.; Marin, Yu. B.

    2014-12-01

    The paper discusses the morphology, anatomy, and geochemistry of zircons from granitic rocks of postorogenic intrusive series with Li-F granites in the Russian Far East. The multiphase Upper Urmi pluton in the Amur region and the Severny pluton in the Chukchi Peninsula have been chosen as reference objects. The directed variations of zircon morphology and geochemistry in the history of Pacific postorogenic granitic magmatism reflect decrease in depth of magma generation and crystallization temperature along with an increase in alkalinity, fluid saturation, and rare-metal potential of granitic melts.

  5. Coastal Erosion Armoring 2005

    Data.gov (United States)

    California Department of Resources — Coastal armoring along the coast of California, created to provide a database of all existing coastal armoring based on data available at the time of creation....

  6. Coastal Erosion Armoring 2005

    Data.gov (United States)

    California Natural Resource Agency — Coastal armoring along the coast of California, created to provide a database of all existing coastal armoring based on data available at the time of creation....

  7. Ultrasonic evaluation of the physical and mechanical properties of granites.

    Science.gov (United States)

    Vasconcelos, G; Lourenço, P B; Alves, C A S; Pamplona, J

    2008-09-01

    Masonry is the oldest building material that survived until today, being used all over the world and being present in the most impressive historical structures as an evidence of spirit of enterprise of ancient cultures. Conservation, rehabilitation and strengthening of the built heritage and protection of human lives are clear demands of modern societies. In this process, the use of nondestructive methods has become much common in the diagnosis of structural integrity of masonry elements. With respect to the evaluation of the stone condition, the ultrasonic pulse velocity is a simple and economical tool. Thus, the central issue of the present paper concerns the evaluation of the suitability of the ultrasonic pulse velocity method for describing the mechanical and physical properties of granites (range size between 0.1-4.0 mm and 0.3-16.5 mm) and for the assessment of its weathering state. The mechanical properties encompass the compressive and tensile strength and modulus of elasticity, and the physical properties include the density and porosity. For this purpose, measurements of the longitudinal ultrasonic pulse velocity with distinct natural frequency of the transducers were carried out on specimens with different size and shape. A discussion of the factors that induce variations on the ultrasonic velocity is also provided. Additionally, statistical correlations between ultrasonic pulse velocity and mechanical and physical properties of granites are presented and discussed. The major output of the work is the confirmation that ultrasonic pulse velocity can be effectively used as a simple and economical nondestructive method for a preliminary prediction of mechanical and physical properties, as well as a tool for the assessment of the weathering changes of granites that occur during the serviceable life. This is of much interest due to the usual difficulties in removing specimens for mechanical characterization.

  8. Characterization of granite waste for use in red ceramic

    International Nuclear Information System (INIS)

    Aguiar, M.C.; Monteiro, S.N.; Vieira, C.M.F.; Borlini, M.C.

    2011-01-01

    This work aims to study the characterization of the granite waste from the city of Santo Antonio de Padua-RJ for the use in red ceramic. The chemical, physical and morphological characterization of the waste was performed by chemical analysis, X-ray diffraction, particle size distribution, thermal analysis and scanning electron microscopy (SEM). The results indicated that this waste is a material with great potential to be used as a component of ceramic body due to its capacity to act as flux during the firing, and to improve the properties of the ceramic when is incorporate. (author)

  9. Interwell tracer analyses of a hydraulically fractured granitic geothermal reservoir

    International Nuclear Information System (INIS)

    Tester, J.W.; Potter, R.M.; Bivins, R.L.

    1979-01-01

    Field experiments using fluorescent dye and radioactive tracers (Br 82 and I 131 ) have been employed to characterize a hot, low-matrix permeability, hydraulically-fractured granitic reservoir at depths of 2440 to 2960 m (8000 to 9700 ft). Tracer profiles and residence time distributions have been used to delineate changes in the fracture system, particularly in diagnosing pathological flow patterns and in identifying new injection and production zones. The effectiveness of one- and two-dimensional theoretical dispersion models utilizing single and multiple porous, fractured zones with velocity and formation dependent effects are discussed with respect to actual field data

  10. Study of deep fracturation of granitic rock mass. Documentary study

    International Nuclear Information System (INIS)

    Bles, J.L.; Landry, J.

    1984-01-01

    This documentary study realized with the financial support of the European Communities and the CEA aims at the utilization of available data for the understanding of the evolution of natural fractures in granitic rocks from the surface to deep underground. The Mt Blanc road tunnel, the EDF's Arc-Isere gallerie, the Auriat deep borehole and the Pyrenean rock mass of Bassies are studied because detailed structural and geological studies have been realized these last 20 years. In this study are more particularly analyzed the relationship between small fractures and large faults, evolution with depth of fracture density and direction, consequences of rock decompression and relationship between fracturation and groundwater

  11. Underground nuclear explosion effects in granite rock fracturing

    International Nuclear Information System (INIS)

    Derlich, S.

    1970-01-01

    On the Saharan nuclear test site in Hoggar granite, mechanical properties of the altered zones were studied by in situ and laboratory measurements. In situ methods of study are drillings, television, geophysical and permeability measurements. Fracturing is one of the most important nuclear explosion effects. Several altered zones were identified. There are: crushed zone, fractured zone and stressed zone. Collapse of crushed and fractured zone formed the chimney. The extent of each zone can be expressed in terms of yield and of characteristic parameters. Such results are of main interest for industrial uses of underground nuclear explosives in hard rock. (author)

  12. Granite ascent and emplacement during contractional deformation in convergent orogens

    Science.gov (United States)

    Brown, Michael; Solar, Gary S.

    1998-09-01

    Based on a case study in the Central Maine Belt of west-central Maine, U.S.A., it is proposed that crustal-scale shear zone systems provide an effective focussing mechanism for transfer of granite melt through the crust in convergent orogens. During contractional deformation, flow of melt in crustal materials at depths below the brittle-plastic transition is coupled with plastic deformation of these materials. The flow is driven by pressure gradients generated by buoyancy forces and tectonic stresses. Within the oblique-reverse Central Maine Belt shear zone system, stromatic migmatite and concordant to weakly discordant irregular granite sheets occur in zones of higher strain, which suggests percolative flow of melt to form the migmatite leucosomes and viscous flow of melt channelized in sheet-like bodies, possibly along fractures. Cyclic fluctuations of melt pressure may cause instantaneous changes in the effective permeability of the flow network if self-propagating melt-filled tensile and/or dilatant shear fractures are produced due to melt-enhanced embrittlement. Inhomogeneous migmatite and schlieric granite occur in zones of lower strain, which suggests migration of partially-molten material through these zones en masse by granular flow, and channelized flow of melt carrying entrained residue. Founded on the Central Maine Belt case study, we develop a model of melt extraction and ascent using the driving forces, stress conditions and crustal rheologies in convergent, especially transpressive orogens. Ascent of melt becomes inhibited with decreasing depth as the solidus is approached. For intermediate a(H 2O) muscovite-dehydration melting, the water-saturated solidus occurs between 400 and 200 MPa, near the brittle-plastic transition during high- T-low- P metamorphism, where the balance of forces favors (sub-) horizontal fracture propagation. Emplacement of melt may be accommodated by ductile flow and/or stoping of wall rock, and inflation may be accommodated

  13. Characterizing gas permeability and pore properties of Czech granitic rocks

    Czech Academy of Sciences Publication Activity Database

    Konečný, Pavel; Kožušníková, Alena

    2016-01-01

    Roč. 13, č. 4 (2016), s. 331-338 ISSN 1214-9705 R&D Projects: GA ČR GA105/09/0089; GA MŠk(CZ) LO1406; GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : granitic rocks * permeability * pore properties Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.699, year: 2016 https://www.irsm.cas.cz/materialy/acta_content/2016_doi/Konecny_AGG_2016_0015.pdf

  14. Origin and tectonic implications of the ∼200 Ma, collision-related Jerai pluton of the Western Granite Belt, Peninsular Malaysia

    Science.gov (United States)

    Jamil, Azmiah; Ghani, Azman A.; Zaw, Khin; Osman, Syamir; Quek, Long Xiang

    2016-09-01

    Triassic granitoids (∼200-225 Ma) are widespread in the Western Belt of Peninsular Malaysia. The Main Range granite is the biggest batholith in the Western Belt composed of peraluminous to metaluminous granite and granodiorite and displays typical ilmenite-series characteristics. Jerai granitic pluton occurs at the northwestern part of the Main Range granite batholith. The Jerai granite can be divided into three facies: (i) biotite-muscovite granite; (ii) tourmaline granite; and (iii) pegmatite and aplopegmatite. Biotite-muscovite granite accounts for 90% of the Jerai pluton, and the rest is tourmaline granite. Geochemical data reveal that pegmatite and tourmaline granite are more differentiated than biotite-muscovite granite. Both pegmatite and tourmaline granite have a higher SiO2 content (70.95-83.94% versus 69.45-73.35%) and a more pronounced peraluminous character. The U-Pb zircon geochronology of the Jerai granite gave an age ranging from 204 ± 4.3 Ma, 205 ± 4 Ma and 205 ± 2 Ma for pegmatite biotite-muscovite granite and tourmaline granite, respectively. The biotite-muscovite Jerai granites are similar to S-type Main Range granite, but the tourmaline granite has a signature of late-stage hydrothermal fluid interaction such as tourmaline quartz pods, the accumulation of large pegmatitic K-feldspar, pronounced peraluminous character, higher SiO2 content. Age evidence of these two granitic facies suggest that they are from the same magma.

  15. Heat production in granitic rocks: Global analysis based on a new data compilation

    Science.gov (United States)

    Artemieva, I. M.; Thybo, H.; Jakobsen, K.; Sørensen, N. K.; Nielsen, L. S. K.

    2017-12-01

    Granitic rocks play special role in the evolution of the Earth and its thermal regime. Their compositional variability provides constraints on global differentiation processes and large scale planetary evolution, while heat production by radioactive decay is among the main heat sources in the Earth. We analyze a new global database GRANITE2017 on the abundances of Th, U, K and heat production in granitic rocks based on all available published data. Statistical analysis of the data shows a huge scatter in all parameters, but the following conclusions can be made. (i) Bulk heat production in granitic rocks of all ages is ca. 2.0 microW/m3 . It is very low in Archean-Early Proterozoic granitic rocks and there is a remarkable peak in Middle Proterozoic granites followed by a gradual decrease towards Cenozoic granites. (ii) There is no systematic correlation between the tectonically controlled granite-type and bulk heat production, although A-type (anorogenic) granites are the most radioactive, and many of them were emplaced in Middle Proterozoic. (iii) There is no systematic correlation between heat flow and concentrations of radiogenic elements. (iv) The present-day global average Th/U value is 4.75 with a maximum in Archean-Early Proterozoic granites (5.75) and a minimum in Middle-Late Proterozoic granites (3.78). The Th/U ratio at the time of granite emplacement has a minimum in Archean (2.78). (v) The present-day K/U ratio is close to a global estimate for the continental crust only for the entire dataset (1460), but differs from the global ratio for each geological time. (vi) We recognize a sharp change in radiogenic concentrations and ratios from the Early Proterozoic to Middle Proterozoic granites. The Proterozoic anomaly may be caused by major plate reorganizations possibly related to the supercontinent cycle when changes in the granite forming processes may be expected, or it may even indicate a change in global thermal regime, mantle dynamics and plate

  16. Study of deep fractures of granitic rocks: structural study of Saint-Sylvestre granite fractures (Fanay-Augeres and Margnac Mines, Haute-Vienne, France)

    International Nuclear Information System (INIS)

    Bles, J.L.; Dutartre, P.; Feybesse, J.Y.; Gros, Y.; Martin, P.

    1984-01-01

    Radioactive waste disposal in deep geologic formation requires a good knowledge of the host rock characteristics. The present study, concentrated on granitic formations, looks for extrapolation in deep underground of fracturation data obtained at the surface

  17. Comparative study of dark patinas on granitic outcrops and buildings

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, B. [Dpto. Edafologia y Quimica agricola, Fac. Farmacia, Univ. Santiago de Compostela, 15782-Santiago de Compostela (Spain)]. E-mail: edprieto@usc.es; Aira, N. [Dpto. Edafologia y Quimica agricola, Fac. Farmacia, Univ. Santiago de Compostela, 15782-Santiago de Compostela (Spain); Silva, B. [Dpto. Edafologia y Quimica agricola, Fac. Farmacia, Univ. Santiago de Compostela, 15782-Santiago de Compostela (Spain)

    2007-08-01

    Formation of dark patinas on rocky surfaces is mainly related to the deposition of gases and particles and to sulphation mechanisms. In the present study, samples of dark patinas taken from granitic outcrops and from granitic buildings were examined in an attempt to understand the mechanisms of their formation. The outcrops are located in non-polluted areas and are characterized by the absence of any extraneous material that provides calcium, such as e.g. mortar. The buildings are located in areas with low levels of pollution. The climate in the study area favours proliferation of microorganisms. Important differences between the patinas sampled from outcrops and from buildings were observed, as the former are of biological origin and the latter of anthropogenic origin. Although the levels of pollution are low in the sampling area, sulphur was present in all of the samples from urban buildings. Sulphur was not present in patinas from outcrops or in patinas from monuments that are assumed to behave as outcrops (dolmens), although the latter are also of anthropogenic origin. Finally, the patinas were found to be formed by elements accumulated on the surface and not from elements contained within the rock itself.

  18. In-situ diffusion in granite: results from scoping experiments

    International Nuclear Information System (INIS)

    Cramer, J.J.; Melynk, T.W.; Miller, H.G.

    1997-03-01

    This report describes the scoping experiments carried out, both in the laboratory and in-situ at a depth of ∼450 m in the Underground Research Laboratory, for the study to determine the diffusion parameters of intact granite/granodiorite under natural high-stress conditions. The study includes four in-situ diffusion experiments (one each in four separate boreholes with experiment times from six months to two years), and supporting laboratory experiments. Tentative conclusions from the first 203-day in-situ experiment in hole DIF4 indicate that the in-situ tortuosity value of granodiorite under high stress conditions may be significantly higher than those obtained from measurements on the same rock under ambient conditions in the laboratory. Because problems were encountered during drilling of the in-situ sample core, potentially adversely affecting the analytical data, further work needs to be carried out to substantiate these tentative conclusions. Tortuosity values obtained in the laboratory for de-stressed rock from the in-situ experiment zones range between 2.4 and 4.6, falling well within the range of tortuosity values reported by Davison et al. (1994) that were used for the assessment modelling of the reference disposal system (Goodwin et al. 1994). The granodiorite samples have lower tortuosity values (between 2.4 and 3.9) compared with that of the single granite sample (4.6). (author)

  19. Technical concept for rock mechanics tests, Climax Granite, NTS

    Energy Technology Data Exchange (ETDEWEB)

    Hearst, J.R.

    1979-02-01

    If we are to believe our predictions of the thermomechanical behavior of the material surrounding a nuclear waste repository in granite, we must test the computational methods used in making the predictions. If thermal loadings appropriate to a real repository are used, thermally induced displacements and strains are quite small, and available geotechnical instrumentation is only marginally able to measure these effects to the accuracy desired to make thorough tests of the predictions. We outline a three-step program to address these issues. (1) Conduct experiments in which the thermal loading is large compared to that induced by a real repository. This will permit us to make accurate measurements with available instrumentation. (2) Simultaneously, develop improved instrumentation that will enable us to make accurate measurements of motions induced by thermal loadings appropriate to a real repository. (3) Finally, conduct a second set of experiments, with the improved instrumentation and thermal loading similar to that of a real repository in granite. If we can predict the effects of this thermal loading to a few percent over distances of tens of meters for time periods of a few years, and demonstrate that these predictions are correct, we can have reasonable confidence that, using the same methods, we can predict the behavior over thousands of meters for hundreds of years to an order of magnitude. That accuracy should be satisfactory for those distances and times.

  20. Desorption of cesium from granite under various aqueous conditions

    International Nuclear Information System (INIS)

    Wang, T.-H.; Li, M.-H.; Wei, Y.-Y.; Teng, S.-P.

    2010-01-01

    In this work the desorption of cesium ions from crushed granite in synthetic groundwater (GW) and seawater (SW) was investigated. Results were compared with those obtained in deionized water (DW) and in two kinds of extraction solutions, namely: MgCl 2 and NaOAc (sodium acetate). In general, the desorption rate of Cs from crushed granite increased proportionally with initial Cs loadings. Also, amounts of desorbed Cs ions followed the tendency in the order SW>GW>NaOAc∼MgCl 2 >DW solutions. This indicated that the utilization of extraction reagents for ion exchange will underestimate the Cs desorption behavior. Fitting these experimental data by Langmuir model showed that these extraction reagents have reduced Cs uptake by more than 90%, while only less than 1% of adsorbed Cs ions are still observed in GW and SW solutions in comparison to those in DW. Further SEM/EDS mapping studies clearly demonstrate that these remaining adsorbed Cs ions are at the fracture areas of biotite.

  1. Alteration, fracture infills and weathering of the Strath Halladale granite

    International Nuclear Information System (INIS)

    Storey, B.C.; Lintern, B.C.

    1981-12-01

    The Strath Halladale Granite has undergone a complex history of faulting, alteration and weathering. The alteration varies from thin ramifying veins and irregular diffuse areas within fresh rock to alteration zones in which all the major phases have been partially or completely replaced. Initial reactions were associated with magmatic fluids which formed pegmatites and aplites within extensional fractures. Introduction of meteoric waters resulted in the formation of a convecting hydrothermal system driven by a magmatic heat energy source. The migrating fluids formed secondary dioctahedral micas and chlorite within the granite, and calcite, siderite, iron sulphide, iron oxides, smectites and quartz within the brittle fractures. Many fractures are shear zones which are infilled by granulated quartz, feldspar and mica. The presence of montmorillonite, the lowest temperature mineral phase, and a preliminary study of stable isotopes indicate temperatures in excess of 100 deg C for migrating alkali-rich fluids. In an assessment of the feasibility of the disposal of high level radioactive waste the ubiquitous presence of montmorillonite, which has a high sorption capacity, is important. (author)

  2. Forsmark site investigation. Granitic groundwater colloids sampling and characterisation

    International Nuclear Information System (INIS)

    Nilsson, A.C.; Degueldre, C.

    2007-08-01

    Natural ground water colloids were sampled by micro-filtration of water samples collected from a granitic groundwater and maintained at the in situ thermodynamic conditions. The methodology avoids the generation of artefacts produced by pH changes due to CO 2 exchange, yielding potential carbonate precipitation, or by O 2 contaminations yielding oxidized insoluble phases. The enhanced pressure and the anoxic conditions are maintained also through the filtering procedure. In situ groundwater sampling followed by micro-filtration of the colloids were carried out after a period of regular sampling of groundwater pumped to the ground surface and continuous on-line long-term measurements (weeks, months) of chemical and physical parameters in the unbroken sample water both at the ground surface and at depth down-hole. Colloid samples were characterized by scanning electron microscopy. At deep granitic groundwater conditions, natural colloids occur sparsely. The colloid concentration was determined C col ∼1 μg/L for sizes ranging from 50 to 500 nm or N col ∼10 8 /L for sizes larger than 100 nm. These colloids are clay with an average size smaller than 200 nm. For the Na-Ca-Cl groundwater (pH 7.53, ionic strength ∼0.1M), the colloid concentration values are comparable with values reported earlier in the literature

  3. Geology and geochronology of the granitic batholithic complex, Sinaloa, Mexico

    International Nuclear Information System (INIS)

    Henry, C.D.

    1975-01-01

    Geologic mapping shows that a large portion of the state of Sinaloa, Mexico is underlain by a granitic batholithic complex. It is predominantly granodiorite, though ranging in composition from gabbro to quartz monzonite. Pre-batholithic rocks include metamorphosed eugeosynclinal sedimentary rocks (Early Cretaceous or older), a mafic igneous complex of gabbro, pyroxenite, and anorthosite, and a quartz diorite orthogneiss. Relative age relationships among these rock types are uncertain. The pre-batholithic rocks are restricted to a belt along the Pacific coast. Comparisons of biotite and hornblende K--Ar ages and zircon U--Pb ages from identical samples reveal that concordant biotite-hornblende K--Ar ages (ages that agree within analytical precision) measure a time during cooling of a granitic rock that closely followed emplacement and crystallization. Cooling of a small (3 km diameter) pluton emplaced in a relatively cold environment was rapid, and K--Ar and U--Pb ages agree within approximately 1 million years. Two larger plutons (30 to 40 km in diameter) that were studied in detail were emplaced into hot environments. They cooled more slowly, such that the K--Ar ages of biotite and hornblende are 3 to 4 million years lower than the U--Pb ages of zircon

  4. Hydrogeologic characterization of a fractured granitic rock aquifer, Raymond, California

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, Andrew J.B. [Univ. of California, Berkeley, CA (United States)

    1993-10-01

    The hydrogeologic properties of a shallow, fractured granitic rock aquifer in the foothills of the Sierra Nevada, California were investigated via the analysis of borehole geophysical logs and pumping tests. The drawdowns produced during these tests are not indicative of any simple conceptual aquifer model, and borehole logs show that the granite is intensely fractured. These observations are suggestive of a complex fracture-flow geometry which is extremely difficult to decipher. However, through the measurement of orientations of individual subsurface fractures from acoustic televiewer logs, and correlation between particular fractures and electrical resistivity and thermal-pulse flowmeter logs, it was found that the aquifer is, in general, comprised of two subhorizontal and nearly parallel zones of unloading fractures. Downhole flowmeter measurements taken in several wells provide further evidence for the inferred dual-layer structure of the aquifer, as well as yield quantitative measures of the contribution of flow from each zone. Analysis of drawdowns in pumped wells reveals that there are zones of relatively high transmissivity immediately around them. It was found that these properties, as well as a nearby zone of lower transmissivity, can account for their observed drawdowns. A numerical model was constructed to test whether these major heterogeneities could also account for the drawdowns in observation wells. This stepwise analysis of both the geophysical and hydrological data resulted in the formulation of a conceptual model of the aquifer which is consistent with observations, and which can account for its behavior when subjected to pumping.

  5. Permian ultrafelsic A-type granite from Besar Islands group, Johor ...

    Indian Academy of Sciences (India)

    mon and developed mainly along the biotite cleav- age. Occasionally, secondary muscovite crystals can be seen developed in the biotite cleavage. The ...... 10.1016/j.gr.2013.03.019. Orajaka I P 1986 Geochemistry of Kaffo Valley albiteriebeckite-granite, Liruei granite ring-complex, northern Nigeria; Chem. Geol. 56 85–92.

  6. The Taitao Granites: I-type granites formed by subduction of the Chile Ridge and its implication in growth of continental crusts

    Science.gov (United States)

    Anma, Ryo

    2016-04-01

    Late Miocene to Early Pliocene granite plutons are exposed at the tip of the Taitao peninsula, the westernmost promontory of the Chilean coast, together with a contemporaneous ophiolite with a Penrose-type stratigraphy. Namely, the Taitao granites and the Taitao ohiolite, respectively, are located at ~30 km southeast of the Chile triple junction, where a spreading center of the Chile ridge system is subducting underneath the South America plate. This unique tectonic setting provides an excellent opportunity to study the generation processes of granitic magmas at a ridge subduction environment, and the complex magmatic interactions between the subducting ridge, overlying crust and sediments, and mantle. This paper reviews previous studies on the Taitao ophiolite/granite complex and use geochemical data and U-Pb age distributions of zircons separated from igneous and sedimentary rocks from the area to discuss the mechanism that formed juvenile magma of calc-alkaline I-type granites during ridge subduction. Our model implies that the magmas of the Taitao granites formed mainly due to partial melting of hot oceanic crust adjacent to the subducting mid-oceanic ridge that has been under influence of deep crustal contamination and/or metasomatized sub-arc mantle through slab window. The partial melting took place under garnet-free-amphibolite conditions. The juvenile magmas then incorporated a different amount of subducted sediments to form the I-type granites with various compositions. The Taitao granites provide an ideal case study field that shows the processes to develop continental crusts out of oceanic crusts through ridge subduction.

  7. 2005 dossier: granite. Tome: architecture and management of the geologic disposal; Dossier 2005: granite. Tome architecture et gestion du stockage geologique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This document makes a status of the researches carried out by the French national agency of radioactive wastes (ANDRA) about the geologic disposal of high-level and long-lived radioactive wastes in granite formations. Content: 1 - Approach of the study: main steps since the December 30, 1991 law, ANDRA's research program on disposal in granitic formations; 2 - high-level and long-lived (HLLL) wastes: production scenarios, waste categories, inventory model; 3 - disposal facility design in granitic environment: definition of the geologic disposal functions, the granitic material, general facility design options; 4 - general architecture of a disposal facility in granitic environment: surface facilities, underground facilities, disposal process, operational safety; 5 - B-type wastes disposal area: primary containers of B-type wastes, safety options, concrete containers, disposal alveoles, architecture of the B-type wastes disposal area, disposal process and feasibility aspects, functions of disposal components with time; 6 - C-type wastes disposal area: C-type wastes primary containers, safety options, super-containers, disposal alveoles, architecture of the C-type wastes disposal area, disposal process in a reversibility logics, functions of disposal components with time; 7 - spent fuels disposal area: spent fuel assemblies, safety options, spent fuel containers, disposal alveoles, architecture of the spent fuel disposal area, disposal process in a reversibility logics, functions of disposal components with time; 8 - conclusions: suitability of the architecture with various types of French granites, strong design, reversibility taken into consideration. (J.S.)

  8. A fractal derivative constitutive model for three stages in granite creep

    Directory of Open Access Journals (Sweden)

    R. Wang

    Full Text Available In this paper, by replacing the Newtonian dashpot with the fractal dashpot and considering damage effect, a new constitutive model is proposed in terms of time fractal derivative to describe the full creep regions of granite. The analytic solutions of the fractal derivative creep constitutive equation are derived via scaling transform. The conventional triaxial compression creep tests are performed on MTS 815 rock mechanics test system to verify the efficiency of the new model. The granite specimen is taken from Beishan site, the most potential area for the China’s high-level radioactive waste repository. It is shown that the proposed fractal model can characterize the creep behavior of granite especially in accelerating stage which the classical models cannot predict. The parametric sensitivity analysis is also conducted to investigate the effects of model parameters on the creep strain of granite. Keywords: Beishan granite, Fractal derivative, Damage evolution, Scaling transformation

  9. Characteristics and significance of uranium bearing pan african younger granite in the eastern desert, Egypt

    International Nuclear Information System (INIS)

    Hassan, M.A.; Dabbour, G.A.; Mohammden, T.F.

    1998-01-01

    Surficial uranium mineralization was discovered in four pan african younger granite plutons in the eastern desert of egypt. The present study revealed great similarity between these plutons both in petrography and geochemistry. They are two-feldspar, two-mica peraluminous granites which have been formed by melting of crustal materials and emplaced during the late stage stage of a late proterozoic orogenic cycle. Radiometric and geochemical investigations indicate that these granites are fertile with respect to U and form a potential target for primary uranium deposits. Four models are suggested to explain the source and mechanism of the surficial uranium mineralization in these granites. The most applicable model is the oxidation of U +4 found in minute disseminated uraninite grains and its subsequent mobilization. This is supported by petrographic and autoradiographic studies. The bearings of the present study on further exploration for uranium deposits in granites of the arabian- Nubian shield in general are discussed

  10. Radiometric age of granite from Campo Formoso, BA-Brazil - a minimum age for Jacobina group

    International Nuclear Information System (INIS)

    Torquato, J.R.; Oliveira, M.A.F.T. de; Bartels, R.L.

    1978-01-01

    The Campo Formoso granite represents the magmatic phase of the remobilized Pre-Jacobina basement, located within an are defined by the Serra de Jacobina, north of Campo Formoso, Bahia. Intrusive relationships between this granite and the Jacobina Group metasediments, gradational changes in textures and compositions between the granite and basement rocks, and the general structural-topographic expression of this suggest a mantled gneiss dome model for this area. A RB/Sr whole rock isochron age of 1911 +- 13 m.y. for the Campo Formoso granite is established. This date is interpreted as the age of the development of the structure, as well as a minimum age for the Jacobina Group metasediments. K/Ar dates on muscovites from the Campo Formoso granite are concordant with the Rb/Sr isocron. It is suggested that a lower regional thermal gradient in the Campo Formoso area during Transamazonic time is the cause for a more rapid cooling environment. (Author) [pt

  11. The distribution and uranium content characteristics of Indosinian granite in South China

    International Nuclear Information System (INIS)

    Sun Wenliang; Zhang Zhuo; Chen Wenwen; Chen Lulu; Xu Wenzheng

    2014-01-01

    In recent years, more and more Indosinian granite plutons has been found in South China, so some new ideas about the granity were proposed by scholars. The Indosinian granite in South China distributed in lineshape, and is controlled by some regional faults. Its formation was mainly related to geodynamic setting which began in the late Permian (about 256 Ma) by the subduction of the ancient Pacific Plate to the Eurasia. The average uranium content of Indosinian granite is 10.34ppm, much higher than the average value of world's acid rock. There occurs some couplings between the distribution of the Indosinian granite plutons and uranium mineralization belt in South China. So the Indosinian granite in South China may act as important uranium sources for the mineralization. (authors)

  12. 2005 dossier: granite. Tome: safety analysis of the geologic disposal; Dossier 2005: granite. Tome analyse de surete du stockage geologique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    This document makes a status of the researches carried out by the French national agency of radioactive wastes (ANDRA) about the safety aspects of the geologic disposal of high-level and long-lived (HLLL) radioactive wastes in granite formations. Content: 1 - safety approach: context and general goal, references, design approach by safety functions, safety approach during the construction-exploitation-observation-closure phase, safety analysis during the post-closure phase; 2 - general description: HLLL wastes, granitic environment, general structure of the architecture of a disposal facility; 3 - safety functions and disposal design: general context, safety functions of the long-term disposal, design dispositions retained to answer the functions; 4 - operational safety: people's protection, radiological risks during exploitation, risk analysis in accident situation; 5 - qualitative safety analysis: methodology, main results of the analysis of the features, events and processes (FEP) database; 6 - disposal efficiency evaluation during post-closure phase: calculation models, calculation tools used for the modeling of radionuclides transport, calculation results and main lessons. (J.S.)

  13. Mafic microgranular enclaves (MMEs) in amphibole-bearing granites of the Bintang batholith, Main Range granite province: Evidence for a meta-igneous basement in Western Peninsular Malaysia

    Science.gov (United States)

    Quek, Long Xiang; Ghani, Azman A.; Chung, Sun-Lin; Li, Shan; Lai, Yu-Ming; Saidin, Mokhtar; Amir Hassan, Meor H.; Muhammad Ali, Muhammad Afiq; Badruldin, Muhammad Hafifi; Abu Bakar, Ahmad Farid

    2017-08-01

    Mafic microgranular enclaves (MMEs) with varying sizes are a common occurrence in porphyritic amphibole-bearing granite of the Bintang batholith, which is part of the Main Range granite province. The MMEs of the amphibole-bearing granite are significant as they are related to the I-type granitoids within the Main Range granite province. Petrographic observations indicate the MMEs are mantled with coarse mafic crystals on the rim and contain similar minerals to the host (biotite + plagioclase + K-feldspar + pyroxene + amphibole), but in different proportions. Geochemical analyses indicate the MMEs are shoshonitic with mg# comparable to the granite host. Substantial similarities exist between the MMEs and granite with regards to the normalized rare earth element patterns and trace elements variation diagrams. The MMEs and granite are not completely coeval as the MME zircon U-Pb age (224.3 ± 1.2 Ma) is slightly older than its granite host zircon U-Pb age (216.2 ± 1.0 Ma). The age difference is also observed from the unusual 500 m-long Tiak MME and another amphibole-bearing granite sample from the south of the pluton, which yield 221.8 ± 1.1 Ma and 217.4 ± 1.0 Ma respectively. The oldest inherited zircons found in the MME and granite are 2.0 Ga and 1.3 Ga respectively, while the oldest xenocrystic zircons found in the MME and granite are 2.5 Ga and 1.5 Ga respectively. Identical negative εHf(t) values from zircon U-Pb and Lu-Hf analysis for a MME-granite pair indicates the rocks were generated from a similar, ancient source in the basement. Combining the results, we suggest that incongruent melting of an ancient protolith played an important part in the evolution of the MMEs and granite and the MMEs characteristics are best explained as restite. The zircon Hf model age (two-stage) and the I-type peritectic and restitic mineral assemblages in the MMEs further describe the protolith as Early Proterozoic-Late Archean (≈2.5 Ga) meta-igneous rock. This shows the

  14. Mobility of heavy metals through granitic soils using mini column infiltration test

    Science.gov (United States)

    Zarime, Nur'Aishah; Yaacob, W. Z. W.

    2014-09-01

    This study is about the mobility of cadmium through compacted granitic soils. Two granitic soils namely the Broga (BGR) and Kajang (KGR) granitic soils were collected in Selangor, Malaysia. Physical and chemical tests were applied for both granitic soils to determine the physical and chemical properties of soil materials. Physical test results shows granitic soils (BGR and KGR) have high percentage of sand ranging between 54%-63% and 46%-54% respectively, an intermediate and intermediate to high plasticity index as well as high specific gravity ie; 2.50-2.59 and 2.45-2.66 respectively. For chemical test, granitic soils shows acidic pH values ranged from 5.35-5.85 for BGR and pH 5.32-5.54 for KGR. For organic matter, SSA and CEC test, it shows low values ranged from 0.22%-0.34% and 0.39%- 0.50% respectively for organic matter test, 17.96 m2/g-21.93 m2/g and 25.76 m2/g-26.83 m2/g respectively for SSA test and 0.79 meq/100g-1.35 meq/100g and 1.31 meq/100g-1.35 meq/100g respectively for CEC test. Mini column infiltration test was conducted to determine the retention of cadmium while flowing through granite soils. This test conducted based on the falling head permeability concepts. Different G-force ranging from 231G to 1442G was used in this test. The breakthrough curves show the concentration of Cd becomes higher with the increasing of G-force for both granitic samples (BGR and KGR). The selectivity sorption for both granites ranked in the following decreasing order of; 231G>519G>923G>1442G. Results demonstrated that granitic soils also have low buffering capacity due to low resist of pH changes.

  15. Coastal Economic Trends for Coastal Geographies

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These market data provide a comprehensive set of measures of changes in economic activity throughout the coastal regions of the United States. In regard to the...

  16. Gypsum-induced decay in granite monuments in Northwestern Spain

    Directory of Open Access Journals (Sweden)

    Silva Hermo, B.

    2010-03-01

    Full Text Available One of the most common forms of decay in granite monuments is the detachment of the superficial layer of the stone (plaques, plaquettes and scales. Previous studies of granite monuments in the northwest Iberian Peninsula revealed a direct relation between this type of weathering and the presence of calcium sulphate, and a mechanism whereby the salt causes this type of decay was suggested. In the present study, various hypotheses as regards the origin of the gypsum found in granite monuments are proposed. The study involved analysis of the contents of ions soluble in water, the results of X-ray diffraction analyses and the ratios of CaO/SO3 in samples of stone, mortar and deposits collected from different monuments. It was concluded that in most cases the gypsum originated from old paintworks or/and from the joint mortars, although inputs from other sources cannot be discounted, as discussed

    Una de las formas de deterioro más frecuente en los monumentos graníticos es la separación de la capa superficial de la piedra (placas, plaquetas y escamas. En trabajos anteriores centrados en monumentos del noroeste de la Península Ibérica, se constató la relación directa entre esta forma de alteración y la presencia de sulfato de calcio y se propuso el mecanismo a través del cual esta sal provoca este tipo de deterioro. En este trabajo se plantean varias hipótesis acerca del origen del yeso encontrado en monumentos graníticos. Para ello se comparan los contenidos de iones solubilizados en agua, los resultados de difracción de rayos X y las relaciones OCa/SO3 de muestras de piedra, morteros y depósitos recogidas en diferentes monumentos. Se llega a la conclusión de que en la mayor parte de los casos el yeso procede de antiguas pinturas o de revestimientos superficiales y de los morteros de juntas entre sillares, pero no se puede descartar la contribución de otros aportes, los cuales se discuten también en este artículo.

  17. Mineralogical Control on Microbial Diversity in a Weathered Granite?

    Science.gov (United States)

    Gleeson, D.; Clipson, N.; McDermott, F.

    2003-12-01

    Mineral transformation reactions and the behaviour of metals in rock and soils are affected not only by physicochemical parameters but also by biological factors, particularly by microbial activity. Microbes inhabit a wide range of niches in surface and subsurface environments, with mineral-microbe interactions being generally poorly understood. The focus of this study is to elucidate the role of microbial activity in the weathering of common silicate minerals in granitic rocks. A site in the Wicklow Mountains (Ireland) has been identified that consists of an outcrop surface of Caledonian (ca. 400 million years old) pegmatitic granite from which large intact crystals of variably weathered muscovite, plagioclase, K-feldspar and quartz were sampled, together with whole-rock granite. Culture-based microbial approaches have been widely used to profile microbial communities, particularly from copiotrophic environments, but it is now well established that for oligotrophic environments such as those that would be expected on weathering faces, perhaps less than 1% of microbial diversity can be profiled by cultural means. A number of culture-independent molecular based approaches have been developed to profile microbial diversity and community structure. These rely on successfully isolating environmental DNA from a given environment, followed by the use of the polymerase chain reaction (PCR) to amplify the typically small quantities of extracted DNA. Amplified DNA can then be analysed using cloning based approaches as well as community fingerprinting systems such as denaturing gradient gel electrophoresis (DGGE), terminal restriction fragment length polymorphism (TRFLP) and ribosomal intergenic spacer analysis (RISA). Community DNA was extracted and the intergenic spacer region (ITS) between small (16S) and large (23S) bacterial subunit rRNA genes was amplified. RISA fragments were then electrophoresed on a non-denaturing polyacrylamide gel. Banding patterns suggest that

  18. Origin of granite at Cabo de Santo Agostinho, Northeast Brazil

    Science.gov (United States)

    Long, Leon E.; Sial, Alcides N.; Nekvasil, Hanna; Borba, Glicia S.

    1986-09-01

    A 4 km2 exposure of shallowly-emplaced leucogranite on the Atlantic coast at Cabo de Santo Agostinho, 30 km south of Recife, Brazil has been extensively studied chemically and isotopically. Twenty-three major-element analyses indicate that the Cabo granite ranges from peralkaline to peraluminous; Na2O+K2O is very high (7.4 to 10.4 wt.%), with CaO low (˜0.3%) and MgO vanishing (<0.06%). Microprobe analyses confirm the presence of arfvedsonite (biotite absent), and nearly total absence of plagioclase. The rocks are moderately to highly enriched in LREE (La 45 to 350 times chondritic), with extremely pronounced negative Eu anomalies (Eu/Eu*=0.02 to 0.07). Whole-rock δ 18O is consistent at +8.5±0.3%.oSMOW A Rb-Sr isochron age of isotopically slightly disturbed samples is 104.8±1.8 Ma, with initial87Sr/86Sr=0.7084±0.0011. Sr is depleted (2 20 ppm) but Ba is 200 750 ppm. Crystallization path calculations and petrographic observations suggest that magma formed at a pressure close to 6 kbar but rose to a crustal level equivalent to roughly 1 kbar. Quartz, the liquidus phase at moderate H2O concentrations and pressures above 2 kbar, was resorbed during decompression as the magma moved upwards. Ultimately, quartz and alkali feldspar coprecipitated. Feldspar was not retained in the source rock nor removed early from the fractionating magma. Therefore the strong negative Eu anomaly and low Sr abundance are characteristics inherited from the source. A high H2O concentration necessary for a large degree of melting was lacking, hence the Cabo magma composition must reflect a small degree of partial melting of a rather quartz-rich rock such as a feldspathic arenite. In a pre-drift reconstruction of Gondwanaland, the Cabo granite fits on the southernmost and youngest end of the trend of the Niger-Nigerian igneous centers with which it has close affinity. The Cabo granite occupies the western end of the trace of the ancestral Ascension mantle plume which presumably served as

  19. Geochronology and petrogenesis of the Early Cretaceous A-type granite from the Feie'shan W-Sn deposit in the eastern Guangdong Province, SE China: Implications for W-Sn mineralization and geodynamic setting

    Science.gov (United States)

    Liu, Peng; Mao, Jingwen; Santosh, M.; Bao, Zhian; Zeng, Xiaojian; Jia, Lihui

    2018-02-01

    The Feie'shan greisen-type W-Sn deposit in the eastern Guangdong Province forms part of the Southeastern Coastal Metallogenic Belt (SCMB) in South China. Here we present zircon LA-ICP-MS U-Pb geochronology of the biotite granite which shows a weighted mean 206Pb/238U age of 134.7 ± 2.0 Ma, consistent with the zircon U-Pb, biotite 40Ar-39Ar and molybdenite Re-Os ages in the previous study. The biotite granite is peraluminous and belongs to high-K calc-alkaline type. It is characterized by high SiO2, K2O, F, K2O + Na2O and FeOt/(FeOt + MgO), and low CaO, MgO, TiO2 and P2O5 contents, enrichment in Rb, Cs, Th and U, and depletion in Ba, Sr, Zr, Ti and P, with flat REE patterns and distinctly negative Eu anomalies, showing an A2-type affinity. The rocks also display extremely low Ba, Sr and Ti concentrations and high Rb/Sr, Rb/Ba and low CaO/(Na2O + K2O) ratios, indicating high degree of fractionation. Zircon grains from the granite have low Eu/Eu* and Ce4 +/Ce3 + ratios, suggesting low oxygen fugacity. The highly fractionated and reduced features imply that the Feie'shan mineralization is genetically related to the biotite granite. The εNd(t) values and zircon εHf(t) values of the biotite granite range from - 2.96 to - 1.95 and - 5.69 to 0.62, with two-stage Nd and Hf model ages (TDM2) of 1083 to 1164 Ma and 1150 to 1552 Ma, indicating that they were derived from magma hybridization between anatectic granitic and mantle-derived mafic magmas. In combination with previous studies, we propose a geodynamic model for the 145―135 Ma W-Sn mineral system and related magmatism in the southwestern domain of the SCMB. After ca. 145 Ma, the subduction orientation of the Izanagi plate changed from oblique to parallel with respect to the continental margin resulting in large-scale lithosphere extension and thinning, which led to the upwelling of asthenosphere. The ascending mantle-derived mafic magmas provided not only supplied the heat for crustal remelting but also added

  20. Geoscience parameter data base handbook: granites and basalts

    Energy Technology Data Exchange (ETDEWEB)

    1979-12-01

    The Department of Energy has the responsibility for selecting and constructing Federal repositories for radioactive waste. The Nuclear Regulatory Commission must license such repositories prior to construction. The basic requirement in the geologic disposal of radioactive waste is stated as: placement in a geologic host whereby the radioactive waste is not in mechanical, thermal or chemical equilibrium with the object of preventing physical or chemical migration of radionuclides into the biosphere or hydrosphere in hazardous concentration (USGS, 1977). The object of this report is to document the known geologic parameters of large granite and basalt occurrences in the coterminous United States, for future evaluation in the selection and licensing of radioactive waste repositories. The description of the characteristics of certain potential igneous hosts has been limited to existing data pertaining to the general geologic character, geomechanics, and hydrology of identified occurrences. A description of the geochemistry is the subject of a separate report.

  1. Waste disposal in granitic rocks: analysis of thermal microcracks

    International Nuclear Information System (INIS)

    Montoto, M.; Roeshoff, K.; Leojon, B.; Bel-Lan, A.

    1981-04-01

    The possible development of microcracks from a thermal origin has been researched in the granitic rocks of Shipa (Sweden), within which in a real scale have been originated some thermal gradients similar to the ones which could take place in the waste disposal. To achieve an optimal fratographic information, with some petrographic meaning, different microscopic techniques, optical and electronic, have been combined and an automatized quantification methodology has also been developed by means of digitals. Between warmed and unwarmed granitis no microfractographic differences have been detected. The observed variations are only apparent and may be explained as a function of the inherent petrographic heterogeneity of rocky blocks. In any case in the internal temperatures generated within these rocks have not attained its own threshold of thermal microcracking. (author)

  2. Geoscience parameter data base handbook: granites and basalts

    International Nuclear Information System (INIS)

    1979-12-01

    The Department of Energy has the responsibility for selecting and constructing Federal repositories for radioactive waste. The Nuclear Regulatory Commission must license such repositories prior to construction. The basic requirement in the geologic disposal of radioactive waste is stated as: placement in a geologic host whereby the radioactive waste is not in mechanical, thermal or chemical equilibrium with the object of preventing physical or chemical migration of radionuclides into the biosphere or hydrosphere in hazardous concentration (USGS, 1977). The object of this report is to document the known geologic parameters of large granite and basalt occurrences in the coterminous United States, for future evaluation in the selection and licensing of radioactive waste repositories. The description of the characteristics of certain potential igneous hosts has been limited to existing data pertaining to the general geologic character, geomechanics, and hydrology of identified occurrences. A description of the geochemistry is the subject of a separate report

  3. Radon release from granites in south-west England

    CERN Document Server

    Poole, J

    2001-01-01

    accessory minerals. The enhancement of surface area was attributed to the alteration of feldspar to sericite. This has implications for the release of radon. It is thought that the large surface area provides a sink for the adsorption of radon, retaining it in the rock structure. This radon retention explains the paradoxical decline in radon release at small particle size/large specific surface area. Various mechanisms for radon emanation are discussed with reference to the Cornubian granites. It is shown that, based on the measured specific surface areas, inter-crystalline diffusion is a slow process and not a significant contributor to overall radon release (0.01%). Approximately 1% of the total radon produced can be attributed to direct recoil processes, based on the calculated recoil ranges (36 nm). The remainder was attributed to diffusion processes through crystal imperfections and dislocations. The microscopic scale model developed here is extended to the macroscopic scale through examination of the la...

  4. Mechanical property and cutting rate of microwave treated granite rock

    Directory of Open Access Journals (Sweden)

    Lek Sikong

    2009-10-01

    Full Text Available The purpose of this study is to investigate the effect of microwave treatment, especially at low power level on compressive strength and cutting rate of granite rock by using multimodal cavity. The power level and cooling rate of treated samples were found to have an effect on the compressive strength, and the cutting rate. This effect is due to the induction of the plastic zones and micro cracks in the rock matrix, especially at the grain boundaries induced by the thermal stresses of rock forming minerals which have the difference in dielectric properties after microwave heating for a certain exposure time together with the thermal-shock treatment after the heating. It was found that the strength of treated granite is less than 60% of the original after 30 minutes of exposure.The dry heated samples with a water quenching seem to be the most affected samples. They exhibit a significant decrease in compressive strength up to 70% and cutting rate up to 38% after 30-minute treatment at the power of 850W, and after 10-minute treatment at the power of 600W respectively. Prolonged treatment causes the relaxation of induced thermal stresses in the rock mass, leading to a slight increase in compressive strength, and a slight decrease in cutting rate. For dry samples, the cutting rate can be enhanced because of a decrease in hardness of rock mass dropped from 61.5 to 55.4 HRC afterthe 10-minute heating at 600W with thermal shock treatment.The absorbed water in the pores of rock mass also has an effect on a decrease in compressive strength. Because micro cracks developed by the water vapor generated by heat which escapes through open pores. However, it seems to have less effect on the cutting rate because it causes a slight decrease in the hardness.

  5. Thermal cracking of Westerly granite: from physical to numerical experiment

    Science.gov (United States)

    Schrank, Christoph; Fusseis, Florian; Karrech, Ali; Revets, Stefan; Regenauer-Lieb, Klaus; Liu, Jie

    2010-05-01

    Laboratory experiments provide some of the most comprehensive constraints on rock properties such as permeability, porosity, and rheology. However, in most cases such experiments are performed on length and time scales that are much smaller than geological scales. Upscaling, physically sound methods for extrapolation, of the obtained constitutive laws is therefore a matter of hot debate. Here, we present a numerical approach for the upscaling of the porosity evolution due to thermal cracking of Westerly granite. This project draws upon actual laboratory step-heating experiments of Westerly granite observed with high-resolution 3D synchrotron tomography (see Fusseis and others:" Formation of secondary porosity in 4D Synchrotron X-ray tomography experiments"). First, we use tomography time-series data to calibrate numerical simulations at the laboratory scale. In effect, the real-world sample is discretised and "heated" numerically. The software is an implicit Lagrangian finite-element code (Abaqus Standard) using elastoplastic rheologies in coupled temperature-displacement analysis. To minimize computational costs, indirect feedbacks, namely temperature-dependent functions of density, coefficient of thermal expansion, specific heat capacity, Poisson's ratio, and Young's modulus, are pre-calculated with PerpleX (Connolly 2005) and implemented as table input. Direct feedbacks are computed in the framework of thermodynamic equations and solved for explicitly. Next, we repeat the above numerical experiments for simplified stochastic models of the actual sample at the laboratory scale. Finally, we generate stochastic numerical models on increasing scales to determine the scale at which rock properties remain constant regardless of the specific microstructure. This empirical homogenization allows the derivation of constitutive laws which can be employed for large-scale simulations. In this contribution, we will briefly outline this workflow and present first results for

  6. Durability of two water repelents applied to granite

    Directory of Open Access Journals (Sweden)

    Rivas, T.

    1998-06-01

    Full Text Available The durability of two water-repellents for granitic stonework was determined. Weathered and sound samples of granites widely used in building construction and restoration in Galicia (NW Spain were treated with water repellents of known efficacy, and then subjected to two artificial weathering tests: prolonged exposure to UV light, and sodium sulphate crystallization cycles. In both tests, but especially in the salt crystallization cycles, both treatments rapidly lost their water-repellency. Furthermore, the hydrophobic layer of water repellent impeded salt mobility, favouring fissuration parallel to the treated surface, which was eventually shed in the form of a plaque.

    Se presentan los resultados de la durabilidad de dos tratamientos de hidrofugación aplicados a rocas graníticas ampliamente utilizados en la construcción de edificios en Galicia (Noroeste de España. Tras la evaluación de la eficacia de dichos tratamientos, cuyos resultados se presentaron en un trabajo anterior, se someten las muestras tratadas a dos ensayos diferentes de envejecimiento acelerado: ciclos de exposición a la luz ultravioleta y ciclos de cristalización de sulfato de sodio. Los productos hidrofugantes muestran una escasa resistencia a ambos ensayos, sobre todo a los ciclos de cristalización de sulfato de sodio; esta débil durabilidad se manifiesta en una rápida pérdida de sus propiedades hidrofugantes. Así mismo, se observa que la presencia de la capa hidrófoba en la piedra funciona como una barrera frente a la movilidad de sales, lo que ocasiona el total desprendimiento de aquella y un fuerte deterioro del material rocoso.

  7. Magmatic constraints on localization of natural stone deposits in the Vehmaa rapakivi granite batholith, southwestern Finland

    Directory of Open Access Journals (Sweden)

    Olavi Selonen

    2011-08-01

    Full Text Available The 1580–1570 Ma old Vehmaa rapakivi granite batholith was studied with the aim to define the geological constraints for localization of natural stone deposits in the batholith. The batholith comprises four roughly concentric granite intrusions from the margin inwards: pyterlite, coarse-grained porphyritic rapakivi granite and two types of medium-grained porphyritic rapakivi granite. Also porphyry aplite and even-grained rapakivi granite occur. The batholith has intruded as a succession of pulses of subhorizontal sheet-like intrusions conceivably through repeated cauldron subsidence. Natural stone quarries are confined only to certain intrusions within the batholith. We show that the medium-grained porphyritic granite body in the centre of the batholith comprises two almost identical but different intrusions, with only slightly different appearances: the inner (IG and the outer (OG granite. The quarries are confined to the outer intrusion which has an appearance more attractive to the market than that of the inner intrusion. The localization of the natural stone deposits in the Vehmaa batholith is a result of the magmatic history of the batholith, producing intrusions of different appearances with different commercial potential.

  8. Structural and petrophysical characterisation of granite: intended for radioactive waste stocking

    International Nuclear Information System (INIS)

    Stanek, Martin

    2013-01-01

    Structural and petrophysical analysis have been conducted within the Melechov massif with focus on structures controlling the porosity, permeability and thermal conductivity of the rock. The structure of the massif has been constrained based on extensive dataset including AMS and field structural measurements of ductile and brittle structures. The fracture system of the massif has been described by four sets of fractures. The measured petrophysical data have been used to characterize the effect of fracturing and alteration on pore space geometry and in turn on permeability, thermal conductivity and elastic properties of the studied granite. Distinct petrophysical properties have been identified for pristine granite, for fractured fresh granite as well as for fractured granite altered by Fe-oxide, chlorite and clay minerals. A detailed microstructural study combined with multidirectional P-wave velocity measurements at high confining pressure and with AMS analysis has been conducted on a Schlieren bearing sample of Lipnice granite. The granite VP anisotropy at low confining pressure was controlled by intergranular cracks interconnecting Schlieren-sub parallel cleavage cracks in micas and feldspars and by exfoliation fracture-sub parallel intra- or trans-granular cracks in cleavage-free quartz. Major closing of the crack porosity linked to the Schlieren granite below depth of 500 m has been interpreted in terms of crack compliance reflected by rapid increase in VP with confining pressure. (author)

  9. U-Th mineralisation in Berach Granite around Belwa, Devtalai and Gudalia, Bhilwara, Rajasthan

    International Nuclear Information System (INIS)

    Saini, S.N.; Yadav, G.S.; Fahmi, Sohail

    2008-01-01

    Uranium - thorium mineralization in Belwa, Devtalai and Gudalia areas is hosted in pink phase of Berach Granite (BG) at the western intrusive contact with the rocks of Mangalwar Complex (MC) in the northern apical region of the granite body. It occurs at the foot wall side of copper mineralization that is associated with quartz reefs. Although surface manifestation of mineralization is limited, its subsurface continuity has been traced over 5 km length in between Belwa and Gudalia. Core samples of pink granite have radiometrically assed from 0.014 to 0.036% U 3 O 8 , <0.01 to 0.032% U 3 O 8 and <0.005 to 0.015 ThO 2 . The Berach Granite (BG) has two phases. An early grey and later pink phase. The pink variety hosts mineralization and is a high silica, low-Ca and peraluminous granite, while the grey granite is characterised by low-silica and high-Ca content. Mineralisation falls along the Bharatpur-Mount Abu lineament, close to thrust zone of Mangalwars and Jahazpurs. Radioactivity due to uranium and thorium in pink granite is associated with titanomagnetite, zircon, ilmenite and monazite. (author)

  10. Coastal Conditions 2000

    Data.gov (United States)

    California Department of Resources — Dataset developed by California Coastal Commission's Melanie Coyne by attaching names to a dynamically segmented coastline using the Department of Navigation and...

  11. Fan-delta and interdeltaic shoreline sediments of Middle Devonian Granite Wash and Keg River clastics, Red Earth field, north Alberta basin, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Sabry, H.

    1989-03-01

    A detailed sedimentological investigation of over 4000 ft of core and 500 well logs of the Middle Devonian granite wash and Keg River clastics in the Red Earth field, North Alberta basin, Canada, has led to the recognition of a granite wash subaerial fan-delta system that is laterally continuous with a Keg River subaqueous delta component along an eastern shoreline of the ancestral Peace River arch. The subaerial fan delta includes alluvial fan facies, sheet wash and mud flows, and playa lakes. The subaqueous delta component includes lower shoreface, upper shoreface, beach-foreshore, eolian sand dunes, lagoon, washover sands, tidal channels and flats, and supratidal carbonates and anhydrites. Within this system, six mappable units are defined. A conceptual depositional model for the sequence depicts four main events. (1) Erosion of Peach River arch uplifted fault blocks, which produced coarse-grained fan-delta sediments in an adjacent fault-bounded margin. Subsequent fluvial reworking resulted in the deposition of thick, lenticular, wedge-shaped alluvial fans of granite wash. (2) Progradation of alluvial fans seaward into the Keg River Sea. (3) Transgression by Middle Devonian seas from the east, which reworked alluvial fans and led to deposition of discontinuous linear sand bodies represented by the Keg River regressive shoreline sediments. (4) Restriction of the sea by the Presqu'ile barrier reef to the north, which deposited evaporites of the Muskeg Formation over the whole sequence. Modern analog to this fan-delta system is the coastal fans of the Gulf of Aqaba, Red Sea. Red Earth field contains over 27 million bbl of recoverable oil, related to a combination structural-stratigraphic trap.

  12. Contribution of Portuguese two-mica granites to stone built heritage

    Science.gov (United States)

    Almeida, Angela; Begonha, Arlindo

    2013-04-01

    The present study deals with the importance of the application of natural stone in monuments in urban setting, both as the main building material during the historical evolution of a city and as a means to increase the public awareness of the social role of geological resources of a specific region. The City of Oporto, World Heritage of the Humanity , has been selected to illustrate the use of the local granite since ancient times to the present day, a two-mica peraluminous granite ,classified as syn-tectonic relatively to the third tectonic deformation phase of the Hercynian orogeny, included in an expressive group that occurs extensively in northern Portugal . The Oporto granite has been the object of several geochemical, structural and geotechnical approaches. Despite the urban development, outcrops of this granite can be observed in different areas of the city, side by side with the urban constructions, and particularly in the imposing and intensely fractured escarpments carved by the river Douro. Oporto monumental heritage goes back to Roman occupation and the profile has been developed by the construction of granite buildings, following history and the social evolution, of an impressive grey architecture according to different styles of granite work that characterize the city in all its aspects, namely the old city wall, the medieval and baroque churches, the neoclassic houses but also the small humble habitations. The Oporto granite is always affected by weathering processes and the buildings exhibit various aspects of stone decay such as granular desintegration, plates, flakes, black crusts, thin black layers, efflorescences and biological colonization. The description of selected sites within the historical centre , where it is possible to recognize the importance of the granite in the character of the city, aims to call the attention to the inextricable role of geology in built heritage and in the culture, as well as to diagnose the deterioration

  13. Mineralogy, geochemistry and petrophysics of red coloured granite adjacent to fractures

    International Nuclear Information System (INIS)

    Eliasson, T.

    1993-03-01

    Mineralogical, geochemical and petrophysical investigations were conducted of red-coloured alteration rims and of the neighbouring unaltered equivalents along fractures within granite from Aespoe. An investigation was made also of a weak to rather strong, red-coloured granite from the Stripa mine, as well as a weak brownish-red colouration, definitely no hydrothermal in origin, of weathered rinds at a glacial polished rock surface in the Bohus granite. When approaching the fracture planes in the Aespoe granite, the most diagnostic alteration features are * the saussuritisation and Fe-oxyhydroxide staining of plagioclase, * the crystallisation chlorite pseudomorphs after biotite and * the hematisation of magnetite. The porosity within the alteration zones increases generally 2 to 3 times compared with the protolith rock, whereas the densities decrease by some 5 to 10%. The oxidation of magnetite gives as much as a tenfold lowering of the magnetic susceptibility. The red colouration of the Stripa granite is caused by hematite ± Fe-oxyhydroxide formation along microfractures, grain boundaries and, subordinately, the main minerals. Oxidation and re-precipitation of iron liberated during a retrograde muscovitisation of principally chlorite is interpreted to be the cause of the formation of the ferric oxides. The rather homogeneous density and porosity values of the grey and of the red-coloured granites reflect the minor change in the mineralogy when going from fresh into altered granite. Weathering and whitening of plagioclase in the bleached, outer zone and precipitation of small quantities of Fe-oxyhydroxides/hydroxides in the brownish-red zone cause the macroscopic colouration of the weathering rind below the glacial polished rock surface of Bohus granite. There is a marked increase in porosity from the interior fresh (c. 0.4-0.5%) towards the exterior bleached zone (c.1.5-2%) of the subaerialy, weathered Bohus granite surface. The incipient decomposition of

  14. Paleoarchaean rhyolitic volcanism and the origin of the granitic continental crust

    Science.gov (United States)

    Sanchez-Garrido, C.; Stevens, G.; Armstrong, R.; Moyen, J.; Herve, M.; Doucelance, R.

    2009-12-01

    Earth’s continental crust is dominated by granitic (s. s.) rocks with substantial K2O contents and K/Na > 0.6. However, 75% of Earth’s continental crust formed during the Archaean (4.0—2.5 Ga), as sodic Tonalite-Trondhjemite-Granodiorite (TTG) granitoids (K/Na ~ 0.23). It is generally assumed that the more potassic granites arose by intracrustal recycling of this material. This assumption predicts that Earth’s bulk crustal composition remains TTG-like, limiting the volume of granitic material that can form and necessitating that it would be counterbalanced by a substantially larger volume of refractory residua from the partial melting of TTGs. Consequently, the composition of the post-Archaean crust requires an additional source of crustal K2O. Here we present evidence that in the Barberton Greenstone Belt (BGB) in South Africa, TTG magmas were formed concurrently with sub-volcanic granitic and rhyolitic magmas. This granitic magmatism occurred during each of three documented cycles of TTG magmatism at ca 3550, 3450 and 3230 Ma. The granites and rhyolites from each episode display the same major- and trace- element compositions, which preclude their derivation through fractional crystallization or partial melting of a protolith of TTG composition and indicate their source to be potassic clay-bearing sediments derived predominantly from the weathering of mafic rocks. The production of these granitic magmas that lack crustal residency and are destined to erupt, during each tectono-magmatic episode of crust production, provides a path for the accumulation of potassium in volcano-sedimentary depositories, despite the absence of granites in the plutonic record at the time. In the BGB, the orogenic reworking of the first major accumulation of these sediments (the Fig Tree Group) coincided with the last TTG producing event and fertilised the middle and lower crust for the subsequent production of granitic magmas.

  15. Greisen deposits associated to carboniferous post-orogenic granites with mineralization potential, Sierra de Fiambala, Catamarca, Argentina

    International Nuclear Information System (INIS)

    Fogliata, A. S.; Rubinstein, N. R.; Avila, J. C.; Baez, M.

    2008-01-01

    The Fiambala range is located in the central south part of the province of Catamarca, Western Sierras Pampeanas, Argentina. It is largely conformed by Precambrian metamorphic rocks, a Cambrian granitic intrusive, Ordovician basic and ultra basic rocks and epi zonal Carboniferous granites (Los Ratones, El Salto and Ayacucho Granites). The Carboniferous granites are sub alkaline, weakly peraluminous, high silica (except for the porphyritic facies of Los Ratones granite) and moderately enriched in K. Contents of trace elements and REE indicate that El S alto and Ayacucho granites and the granular facies of Los Ratones granite have characteristics of evolved and differentiated granite associated with hydrothermal systems. The variations of trace elements, particularly Sn, W, U, Rb, Ba, Zr and Sr suggest that they correspond to granites with mineralization potential. Genetically linked to these granites there are Sn, W, U and minor base metals greisen deposits. The hydrothermal process that yield to these deposits involved two main alteration stages, beginning with alkali metasomatism follow by greissenization. According to the isotopic ages the hydrothermal processes postdate about 1 Ma the magmatic activity. The analyses of the granites and the associated greisen deposits confirm that the post orogenic carboniferous magmatism is the major metallogenetic control of the ore deposits from the studied area. This metallogenetic control could be a useful tool in prospecting similar deposits in the rest of the Western Sierras Pampeanas. (Author)

  16. Coastal Analysis, Nassau,NY

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Coastal study as defined in FEMA Guides and Specifications, Appendix D: Guidance for coastal Flooding Analyses and Mapping submitted as a result of a coastal study....

  17. NATIONAL COASTAL CONDITION REPORT III

    Science.gov (United States)

    Coastal waers in the US include estuaries, coastal wetlands, coral reefs, ,mangrove and kelp forests, seagrass meadows, and upwelling areas. Critical coastal habitats provide spawning grounds, nurseries, shelter, and food for finfish, shellfish, birds, and other wildlife. The n...

  18. Study on Time-Dependent Behavior of Granite and the Creep Model Based on Fractional Derivative Approach Considering Temperature

    Directory of Open Access Journals (Sweden)

    Zhilei He

    2016-01-01

    Full Text Available Based on mineral components and the creep experimental studies of Three Gorges granite and Beishan granite from different regions of China at various temperatures, the strength and creep property of two types of granites are compared and analyzed. Considering the damage evolution process, a new creep constitutive model is proposed to describe the creep property of granite at different temperatures based on fractional derivative. The parameters of the new creep model are determined on the basis of the experimental results of the two granites. In addition, a sensitivity study is carried out, showing effects of stress level, fractional derivative order, and the exponent m. The results indicate that the proposed creep model can describe the three creep stages of granite at different temperatures and contribute to further research on the creep property of granite.

  19. Preliminary experiences of radionuclide migration with granitic materials: El Berrocal (Spain)

    International Nuclear Information System (INIS)

    Garcia Gutierrez, M.

    1994-01-01

    This report presents the radionuclide migration in granitic rocks used for radioactive waste storage. This project is developed in El Berrocal (Spain). The author studies the absorption process, applies the transport equation, the column migration and analyzes the curves

  20. Characteristics and its uranium metallogenic potential of the granite belt between Bange and Jiali county, tibet

    International Nuclear Information System (INIS)

    Zhao Baoguang; Wang Qin; Liu Zhipeng; Chen Yuliang; Xu Wei

    2012-01-01

    The granite belt between Bange and Jiali county is a composite batholith which intruded at multistage, it con- trolled by several groups of the fault system, the alteration is developed, with the alaskite, aplite, pegmatitic vein intruded, it is type Ⅰ in the beginning of forming, and change to type S in the late time. There is a large of geochemical anomalies of uranium (U>6.8 X 10 -6 ) in Gulu town and Sangba village, of which middle of the granite belt and Bianba county of which east of the granite belt, that anomalies area have 1200 km 2 , 800 km”2 and 1500 km 2 . All the anomalies is considered that its forming relate to batholith and its external contact, so it shows that it has favorite geological conditions for granite type uranium metallogenesis. (authors)

  1. LGR adult trap data - Operation of the adult trap at Lower Granite Dam

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This Bonneville Power Administration (BPA) - funded project pays for NOAA staff to operate the adult salmon trap located in the fish ladder at Lower Granite Dam. The...

  2. Petrogenesis of Malaysian tin granites: geochemistry, fractional crystallization, U-Pb zircon geochronology and tectonic setting

    Science.gov (United States)

    Wai-Pan Ng, Samuel; Searle, Mike; Whitehouse, Martin; Chung, Sun-Lin; Ghani, Azman; Robb, Laurence; Sone, Masatoshi; Oliver, Grahame; Gardiner, Nick; Roselee, Mohammad

    2014-05-01

    The Malaysian tin granites forming the backbone of the Thai-Malay Peninsula has been long recognized with two distinct granitic provinces:- 1. Early Permian to Late Triassic Eastern Province with mainly "I-type" (Hbl)-Bt granites with associated Cu-Au deposits, with subordinate Bt granites hosting limited Sn-W deposits, and 2. Late Triassic Main Range Province with mainly "S-type" Bt granites with associated Sn-W deposits, and subordinate (Hbl)-Bt granites. New geochemical data show that Chappell and White's (1974) I-S granite classification adopted in the existing model does not adequately distinguish the granites from one another as previously implied. Trace element geochemistry and Sr-Nd isotopic compositions show that the Malaysian tin granites in both provinces have transitional I-S characteristics. In addition, they inherited within-plate signature from Cambro-Ordovician Gondwana-related source rocks. Previous ages were obtained by whole rock Rb-Sr and biotite K-Ar geochronology in the 70s and 80s, dating methods that may not accurately represent the crystallization age of granites. We re-sampled the entire Malaysian Peninsula and 40 samples were collected for high-precision U-Pb SIMS dating on extracted zircon grains in order to better constrain the magmatic and tectonic evolution of Southeast Asia. The crystallization ages of the Eastern Province granitoids have been constrained ranging from 220 to 290 Ma, while the Main Range (Western) Province granitoids have ages ranging from 200 to 230 Ma. A progressive westward younging trend is apparent across the Eastern Province, but becomes less obvious in the Main Range Province. Our model suggests two east dipping subduction zones. We suggest that subduction roll-back along the Bentong-Raub suture might account for the westward younging trend, in the Eastern province. A second Late Triassic east-dipping subduction zone beneath western Malaysia is proposed in order to explain the "I-type" components to the Main

  3. Guide of Black granite prospect ion for the department of Florida

    International Nuclear Information System (INIS)

    Bossi, J.; Campal, N.

    1989-01-01

    The black granite prospection project is between the government of Canada and Uruguay agreement (Facultad de Agronomia - Universidad de la Republica). The main objective is the location and mapping of black granite veins to obtain potential deposits. The study of the relations between surface and deep features of these veins. The preparation of a guide to exploration and exploitation plan for mining companies. Reinforce the capacity of research in economic geology as well as increasing the exports by resources jobs

  4. Assessment of occupational exposure in a granite quarry and processing factory.

    Science.gov (United States)

    Tejado, J J; Guillén, J; Baeza, A

    2016-09-01

    Workers in the granite industry face an occupational hazard: silicosis due to the crystalline silica present in inhalable dust. As granite can also present a variable, and occasionally significant, content of naturally occurring radionuclides, they may also face a radiological hazard. In order to assess the risk, a granite industry with a quarry and processing factory was selected to assess the occupational exposure. Three main potential pathways were observed: external irradiation, inhalation of granite dust, and radon exposure. The external dose rate was similar to that in a nearby farming area. A slight increment (0.016-0.076 mSv yr -1 ) was observed in the quarry and stockpile, due to quarry faces and granite blocks. The effective dose due to granite dust inhalation was 0.182  ±  0.009 mSv yr -1 in the worst case scenario (3 mg m -3 dust load in air and no use of filter masks). Thus, the mean value of the effective dose from these two pathways was 0.26 mSv yr -1 , lower than the reference level of 1 mSv yr -1 for the general population. The annual mean value of radon concentration in the indoor air was 33 Bq m -3 . However, during granite processing works the radon concentration can increase up to 216 Bq m -3 , due to mechanical operations (sawing, polishing, sanding, etc). This radon concentration was below the 600 Bq m -3 reference level for action in working places. Therefore, workers in this granite factory face no significant additional radiological exposure, and no-one needs to be designated as occupationally exposed and subject to individual dosimetry.

  5. Geochemical geochronology and genesis of granite from Coronel Murta, Northeast of Minas Gerais, Brazil

    International Nuclear Information System (INIS)

    Soares, A.C.P.; Siga Junior, O.

    1987-01-01

    Geological, petrographic, geochemical (including rare-earth elements) and geochronological data of the Coronel Murta (Northeast Minas Gerais State) post-tectonic intrusive alkalic granites were summarized in order to discuss their genesis. This paper shows that Coronel Murta granites were generated by anatexis of dominantly metasedimentary rocks, in an ensialic environment, as the late results of an intraplate A-type subduction during the Brazilian Cycle. (author) [pt

  6. Development of a geophysical methodology from boreholes for the study of granitic formation storage site

    International Nuclear Information System (INIS)

    Le Masne, D.

    1983-01-01

    The aim of this work is the characterization of the fracturation of a granitic formation by the examination of borehole environment. Two types of methods are used. Methods using one borehole only: well logging (electrical and nuclear). Didier logs (electric dipole-dipole), Eric probes (electromagnetic dipole-dipole) and methods between boreholes (grounding). These methods were applied to two boreholes of 500m and 1000 meters drilled into granite at Auriat (France)

  7. Modeling of lung cancer risk due to radon exhalation of granite stone in dwelling houses

    Directory of Open Access Journals (Sweden)

    Akbar Abbasi

    2017-01-01

    Conclusions: The estimated numbers of lung cancer deaths attributable to indoor radon due to granite stones in 2013 were 145 (3.33% and 103 (2.37% for poor and normal ventilation systems, respectively. According to our estimations, the values of 3.33% and 2.37% of lung cancer deaths in 2013 are attributed to radon exhalation of granite stones with poor and normal ventilation systems, respectively.

  8. Gamma-spectrometric surveys in differentiated granites. II: the Joaquim Murtinho Granite in the Cunhaporanga Granitic Complex, Parana, SE Brazil; Levantamentos gamaespectrometricos em granitos diferenciados. II: O exemplo do Granito Joaquim Murtinho, Complexo Granitico Cunhaporanga, Parana

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Francisco Jose Fonseca [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Geologia. Lab. de Pesquisas em Geofisica Aplicada; Fruchting, Allan [Votorantim Metais, Sao Paulo, SP (Brazil)], e-mail: allan.fruchting@vmetais.com.br; Guimaraes, Gilson Burigo [Universidade Estadual de Ponta Grossa (UEPG), PR (Brazil). Dept. de Geociencias], e-mail: gburigo@ig.com.br; Alves, Luizemara Soares [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)], e-mail: luizemara@petrobras.com.br; Martin, Victor Miguel Oliveira; Ulbrich, Horstpeter Herberto Gustavo Jose [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Geociencias. Dept. de Mineralogia e Geotectonica], e-mail: vicmartin6@ig.com.br, e-mail: hulbrich@usp.br

    2009-07-01

    Detailed mapping at the NW corner of the large Neo proterozoic Cunhaporanga Granitic Complex (CGC), Parana state, SE Brazil, redefined the Joaquim Murtinho Granite (JMG), a late intrusion in CGC with an exposed area of about 10 km{sup 2}, made up mainly by evolved 'alaskites' (alkali-feldspar leuco granites). This unit is in tectonic contact with the Neoproterozoic-Eocambrian volcano-sedimentary Castro Group, to the W, and is intrusive into other less evolved granitic units of the CGC to the E. Petrographically, JMG shows mainly mesoperthite and quartz, with subordinate amounts of altered micas and some accessory phases, mainly zircon. The equi to inequigranular granites are usually deformed with cataclastic textures, are often brecciated, and may have miarolitic structures. Formation of late albite, sericite, carbonate and hematite was caused by deuteric and hydrothermal alteration. A gamma-ray spectrometric survey at 231 stations which measured total counts (TC), Ueq K%, eU ppm and eTh ppm was used to construct several direct and derived maps. Compared to neighboring units the JMG has significant anomalies, especially in the TC, %K, eTh and eU maps, although the differences are less obvious in some derived maps. These evolved granites are enriched in these three elements. Geochemical behavior of K, Th and U is used to analyse the results observed in maps. Enhanced weathering under a subtropical climate with moderate to high average temperatures and heavy rainfall affects mainly feldspars and biotite, and may also destabilize most U and Th-bearing accessory phases. Th is most likely retained in restite minerals in soils, being relatively immobile, while part of U may migrate as uranyl ion in oxidizing media. K is especially affected by feldspar alteration to K-free clays (mainly kaolinite), and may be completely leached. Gamma-ray spectrometric methods are valid tools to study facies in granitic rocks, especially in those that are enriched in K, Th and U

  9. Petrogenesis of Cretaceous (133-84 Ma) intermediate dykes and host granites in southeastern China: Implications for lithospheric extension, continental crustal growth, and geodynamics of Palaeo-Pacific subduction

    Science.gov (United States)

    Yang, Jinbao; Zhao, Zhidan; Hou, Qingye; Niu, Yaoling; Mo, Xuanxue; Sheng, Dan; Wang, Lili

    2018-01-01

    This paper presents U-Pb zircon geochronology, petrology, and major and trace element, Sr-Nd and zircon Hf isotopic geochemistry of Cretaceous granites and intermediate dykes in the Quanzhou and Xiamen regions of southeastern China. These data are used to investigate igneous petrogenesis and Cretaceous tectonic evolution, and interpret the geodynamics of Palaeo-Pacific slab subduction. Granites in Quanzhou and Xiamen range in age from 133 Ma to 87 Ma, have high SiO2 and K2O contents, low abundances in P2O5, and an A/CNK index that ranges from 0.97 to 1.09, indicating that they are high-K calc-alkaline metaluminous I-type rocks. Slightly negative ɛ Nd (t) values (- 1.2 to - 4.4), young Nd model ages (0.87 Ga to 1.20 Ga) and positive ɛ Hf (t) values (- 0.5 to + 9.9) of zircon grains indicate that the granites were derived from magmas that melted amphibolite in the middle-lower crust, and which may have assimilated country rocks during emplacement in shallow chambers. The intermediate dykes have no genetic link to the granites and magma mixing was negligible. Eight dyke samples have low SiO2 and high MgO, Ni and Cr contents. Negative ε Nd (t) values (- 1.5 to - 2.7) and positive ε Hf (t) values (2.7 to 7.6) suggest that the dykes were derived from residual basic lower crust after mafic-crystal accumulation. Two samples of adakite-like dykes are characterised by high Sr/Y ratios (89 to 100) and high SiO2, low K2O, Ni, Cr contents. In combination with slightly negative ε Nd (t) values (- 1.7 to - 1.8) and positive ε Hf (t) values (2.9 to 4.3), the adakite-like dykes were derived from cumulate basic lower crust which had a mixed source between depleted mantle- and crust-derived melts. Based on our data, combined with previously published work, we suggest that extension-induced middle-lower crustal melting and underplating of mantle-derived basaltic melts were the principal driving mechanisms for Cretaceous granitic magmatism in coastal Fujian Province. Extension

  10. The Sao Jose do Rio Pardo mangeritic-granitic suite, south eastern Brazil

    International Nuclear Information System (INIS)

    Campos Neto, M.C.; Figueiredo, M.C.H.; Janasi, V.A.; Basei, M.A.S.; Fryer, B.J.

    1988-01-01

    In the Sao Jose do Rio Pardo region, Sao Paulo and Minas Gerais States, occur some intrusive, folded tabular bodies of mangerites associated with hornblende granitoids. The country rocks correspond to a complex association of gneisses and migmatites, locally with granulite facies assemblages. Both the magnerites and hornblende granitoids present a tectonic foliation with mineral flattening and stretching. Petrographically the mangeritic rocks are mainly dark green quartz mangerites with mesoperthite, plagioclase, quartz, hypersthene, clinopyroxene and variable amounts of hornblende, with zircon as conspicuous acessory. The pink hornblende granitoids are mainly granite s.s. exhibiting higher quartz and amphibole contents and lacking pyroxenes. Hololeucocratic alkali feldspar granites are locally associated to the hornblende granites. The textures of the mangerites and granites almost always show an important metamorphic overprinting, with relictic mesoperthite and pyroxene crystal into a granoblastic matrix. The magneritic-granitic suite is characterized by relatively high Fe/(Fe + Mg), K and HFS elements and low Ca contents, being comparable to typical anorogenic magneritic-granitic suites from Svcandinavia and North America. The Rb/Sr data indicate a Late Proterozoic metamorphic isotopic rehomogenization (930 Ma, Ro = 0.706). Geological evidence suggest that the intrusive age could be Middle Proterozoic, wich is reinforced by another Rb-Sr value of about 1300 Ma. (author) [pt

  11. The role of granites for the ore mineralization in South German Variscides

    International Nuclear Information System (INIS)

    Dill, H.G.

    1987-01-01

    Granites are of widespred occurrence in the South German Variscides (F.R. of Germany), the Black Forest (=BF), and the NE Bavarian Basement (=NEBB). These areas are crossed by the Saxothuringian-Moldanubian plate boundary and were also affected by crustal subdulction and nappe tectonism, both of which are thought to be responsible for granitisation and enrichment of Sn, W,U,Au, Sb,Pb,Zn,F, and Ba in veins of different kind. Heat produced by gliding of plates above each other, by decay of radioctive elements in granites as well as set free by the granites themselves caused the above-mentioned elements to be released from their protores, which formed during Late Proterozoic and Early Paleozoic rifting. These hypogene ore mineralizations may be crudely subdivided into thrustbound, granite-related and granite-induced ore deposites. During Tertiary-Quaternary these granites were exposed the pervasive weathering under subtropical conditions, so that ''U yellow ores'' and china clay deposits came into existence. The whole ore mineralization in that region may be explained by a simple four-step model: preconcentration, fracturation, activation and peneplaination. (author) [pt

  12. ASSESSING LAND COVER CHANGES CAUSED BY GRANITE QUARRYING USING REMOTE SENSING

    Directory of Open Access Journals (Sweden)

    R. S. Moeletsi

    2017-11-01

    Full Text Available Dimension stone quarrying in the area between Rustenburg and Brits in the North West Province of South Africa has been in existence for over 70 decades. The unique characteristics of the granite deposits in South Africa resulted in making the country a global producer of the granite rocks. This led to intensified quarrying activities between Rustenburg and Brits town. However, this surface mining method, has a potential to impact the environment in a negative way causing loss in vegetation, depletion of natural resources, loss of scenic beauty and contamination of surface water resources. To assess the land cover changes caused by granite quarrying activities, remotely sensed data in the form of Landsat images between 1998 and 2015 were used. Supervised classification was used to create maps. Accuracy assessment using Google EarthTM as a reference data yielded an overall accuracy of 78 %. The post classification change detection method was used to assess land cover changes within the granite quarries. Granite quarries increased by 1174.86 ha while formation of quarry lakes increased to 5.3 ha over the 17-year period. Vegetation cover decreased by 1308 ha in area while 18.3 ha bare land was lost during the same period. This study demonstrated the utility of remote sensing to detect changes in land cover within granite quarries.

  13. Modeling and numerical analysis of granite rock specimen under mechanical loading and fire

    Directory of Open Access Journals (Sweden)

    Luc Leroy Ngueyep. Mambou

    2015-02-01

    Full Text Available The effect of ISO 834 fire on the mechanical properties of granite rock specimen submitted to uniaxial loading is numerically investigated. Based on Newton's second law, the rate-equation model of granite rock specimen under mechanical load and fire is established. The effect of heat treatment on the mechanical performance of granite is analyzed at the center and the ends of specimen. At the free end of granite rock specimen, it is shown that from 20 °C to 500 °C, the internal stress and internal strain are weak; whereas above 500 °C, they start to increase rapidly, announcing the imminent collapse. At the center of specimen, the analysis of the internal stress and internal strain reveals that the fire reduces the mechanical performance of granite significantly. Moreover, it is found that after 3 min of exposure to fire, the mechanical energy necessary to fragment the granite can be reduced up to 80%.

  14. Uraniferous alaskitic granites with special reference to the Damara Orogenic Belt

    International Nuclear Information System (INIS)

    Toens, P.D.; Corner, B.

    1980-10-01

    The control and patterns of uranium mineralisation in the alaskitic granites of the Damara Orogenic Belt are discussed. The polyphase Damara metamorphism produced high-grade metamorphic assemblages, migmatites and syn-, late-, and post-tectonic anatectic granites through reactivation of the basement and overlying Damara rocks. During anatexis the incompatible elements, particularly the uranium derived from these formations, were incorporated into the melts which then rose, in an attempt to attain gravitational equilibrium, by varying distances depending on the depth of origin of the melts, on their water content and on the availability of tensional environments. Fractional crystallisation during ascent and increased water content concentrated the uranium into residual melts which finally crystallised as alaskitic pegmatitic granite. Structural episodes played an important part in the emplacement of the uraniferous granites and the presence of marble bands was an important factor in not only providing a structural trap for the alaskitic melts and associated uranium-rich volatiles, but also by leading to the boiling of the magma and the subsequent deposition of uranium. The present-day level of erosion is considered to be an important factor contributing to the preservation of many of the uraniferous granite bodies. In addition it is suggested that secondary enrichment occurring above the water-table in the prevailing desert environment is an important criterion in enriching the tenor of mineralisation to ore grades. The exploration techniques necessary for the location of uraniferous granite bodies are briefly outlined [af

  15. Coastal Hazards: Hurricanes, Tsunamis, Coastal Erosion.

    Science.gov (United States)

    Vandas, Steve

    1998-01-01

    Details an ocean-based lesson and provides background information on the designation of 1998 as the "Year of the Ocean" by the United Nations. Contains activities on the poster insert that can help raise student awareness of coastal-zone hazards. (DDR)

  16. Coastal Geographic Structures in Coastal-Marine Environmental Management

    Science.gov (United States)

    Baklanov, P. Ya.; Ganzei, K. S.; Ermoshin, V. V.

    2018-01-01

    It has been proposed to distinguish the coastal geographic structures consisting of a spatial combination of three interconnected and mutually conditioned parts (coastal-territorial, coastal, coastal-marine), which are interlinked with each other by the cumulative effect of real-energy flows. Distinguishing specific resource features of the coastal structures, by which they play a connecting role in the complex coastalmarine management, has been considered. The main integral resource feature of the coastal structures is their connecting functions, which form transitional parts mutually connecting the coastal-territorial and coastalmarine environmental management.

  17. Polishing Knowledge: A Study of Marble and Granite Processing

    Directory of Open Access Journals (Sweden)

    Simone De Bruim Babisk Mezadre

    2014-07-01

    Full Text Available The aim of this article is to understand the work situations and highlight aspects of the knowledge invested by workers when performing marble and granite processing activities. The survey is qualitative and was based on the reality of a small industrial company that deals with processing activities. The case study was based on theoretical and analytical ergology tools by analyzing the organizational documents and safety and health standards that regulate activity. It involved conducting individual interviews with nine workers, organizing a focus group with these workers, and directly observing work for four months while recording a field notebook. The workers’ experiences in the renormalization of working processes, or the introduction of improvements guided by singular aspects of the local work organization, were identified. The workers, through use of oneself, place more importance on meeting deadlines and production targets than on their own safety. Worker competency is directly related to the professional training obtained on the job and is associated with working experience in the absence of an a priori formal education. This article contributes to the field of organizational studies and human resource management because there is a lack of studies on workers from this field that describe the competencies used in actual work. Thus it may guide theoretical and practical management aspects in such working environments and small businesses regarding safer work organization.

  18. Hydraulic testing in granite using the sinusoidal variation of pressure

    International Nuclear Information System (INIS)

    Black, J.H.; Holmes, D.C.; Noy, D.J.

    1982-09-01

    Access to two boreholes at the Carwynnen test site in Cornwall enabled the trial of a number of innovative approaches to the hydrogeology of fractured crystalline rock. These methods ranged from the use of seisviewer data to measure the orientation of fractures to the use of the sinusoidal pressure technique to measure directional hydraulic diffusivity. The testing began with a short programme of site investigation consisting of borehole caliper and seisviewer logging followed by some single borehole hydraulic tests. The single borehole hydraulic testing was designed to assess whether the available boreholes and adjacent rock were suitable for testing using the sinusoidal method. The main testing methods were slug and pulse tests and were analysed using the fissured porous medium analysis proposed in Barker and Black (1983). Derived hydraulic conductivity (K) ranged from 2 x 10 -12 m/sec to 5 x 10 -7 m/sec with one near-surface zone of high K being perceived in both boreholes. The results were of the form which is typical of fractured rock and indicated a combination of high fracture frequency and permeable granite matrix. The results are described and discussed. (author)

  19. Rock mass characterization for storage of nuclear waste in granite

    International Nuclear Information System (INIS)

    Witherspoon, P.A.; Nelson, P.; Doe, T.; Thorpe, R.; Paulsson, B.; Gale, J.; Forster, C.

    1979-02-01

    The rock mass characterization in granite adjacent to an iron mine at Stripa, Sweden is being carried out by four different methods. The mechanical characterization includes monitoring the responses to thermal loading of jointed rock in situ, and mechanical tests on cores from 25 mm to 1 m in diameter. Geological characterization includes detailed surface mapping, subsurface mapping, and core mapping. Geophysical characterization uses a variety of borehole techniques, with emphasis on sonic methods. The hydrologic characterization is done through injection tests, pump tests, water pressure measurements, and controlled inflow tests to tunnels. Since the data are not yet complete, only tentative conclusions can be drawn regarding the best combinations of techniques for rock-mass characterization. Mapping studies are useful in defining continuity and fracture-system geometry. They do not give aperture, a factor significant in terms of both water flow and the displacements due to heating. Of the geophysical techniques, sonic methods appear most effective in fracture definition; other methods, gamma and neutron particularly, give data on radionuclide and water content and need further analysis with geologic and hydrologic data to determine their significance. Hydrologic work yields primarily aperture data, which with fracture geometry can be used to calculate directional permeabilities. Pressure measurements may provide one means of assessing fracture continuity. Finally, laboratory tests on large cores suggest considerable refinement in testing techniques may be needed before stress-aperture data can be extrapolated from laboratory to field

  20. Inelastic deformations of fault and shear zones in granitic rock

    International Nuclear Information System (INIS)

    Wilder, D.G.

    1986-02-01

    Deformations during heating and cooling of three drifts in granitic rock were influenced by the presence of faults and shear zones. Thermal deformations were significantly larger in sheared and faulted zones than where the rock was jointed, but neither sheared nor faulted. Furthermore, thermal deformations in faulted or sheared rock were not significantly recovered during subsequent cooling, thus a permanent deformation remained. This inelastic response is in contrast with elastic behavior identified in unfaulted and unsheared rock segments. A companion paper indicates that deformations in unsheared or unfaulted rock were effectively modeled as an elastic response. We conclude that permanent deformations occurred in fractures with crushed minerals and fracture filling or gouge materials. Potential mechanisms for this permanent deformation are asperity readjustments during thermal deformations, micro-shearing, asperity crushing and crushing of the secondary fracture filling minerals. Additionally, modulus differences in sheared or faulted rock as compared to more intact rock would result in greater deformations in response to the same thermal loads

  1. Characterization of microbial communities in deep groundwater from granitic rock

    International Nuclear Information System (INIS)

    Jain, D.K.; Stroes-Gascoyne, S.; Providenti, M.; Tanner, C.; Cord, I.

    1997-01-01

    The microbial characteristics of deep granitic nutrient-poor groundwater from two boreholes at the Underground Research Laboratory of Atomic Energy of Canada Limited were studied. Scanning electron microscopy of the groundwater samples revealed significant numbers of bacteria of various sizes and shapes, including spherical, rod, and curved shaped. A few bacteria with appendages were also observed. Significant numbers of bacteria (∼l0 5 /mL) were enumerated using acridine orange (AO) staining. An active microbial population was detected with three direct methods and it ranged from 1 to 83% of the AO count, depending on the method used. Culturable aerobic and anaerobic (including facultative) heterotrophic bacteria ranged from 0.06 to 10.2% and 0.008 to 7.35%, respectively, of the AO count. Denitrifying. N 2 - fixing, sulphate-reducing, and iron-precipitating bacteria were present, but no iron-oxidizing bacteria or methanogens could be detected. Tentative identification of 160 isolates using the Biolog system showed a predominance of three Pseudomonas species, P. fluorescens, P. marginalis, and P. corrugata. Phospholipid fatty acid analysis showed that the bacteria in the groundwater samples faced starvation stress. However, laboratory studies showed that these bacteria can efficiently uptake and mineralize organic substrates when supplied. (author)

  2. Coastal mapping handbook

    Science.gov (United States)

    ,; ,; Ellis, Melvin Y.

    1978-01-01

    Passage of the Coastal Zone Management Act of 1972 focused attention on the Nation's coastal land and water areas. As plans for more effective management of the coastal zone evolved, it soon became apparent that improved maps and charts of these areas were needed. This handbook was prepared with the requirements of the entire coastal community in mind, giving greatest attention to the needs of coastal zone managers and planners at the State and local levels. Its principal objective is to provide general information and guidance; it is neither a textbook nor a technical manual, but rather a primer on coastal mapping. This handbook should help planners and managers of coastal programs to determine their mapping requirements, select the best maps and charts for their particular needs, and to deal effectively with personnel who gather data and prepare maps. The sections on "Sources of Assistance and Advice" and "Product and Data Sources" should be especially useful to all involved in mapping the coastal zone. Brief summaries of the mapping efforts of several State coastal zone management programs are included. "Future outlook" discusses anticipated progress and changes in mapping procedures and techniques. Illustrations are inserted, where appropriate, to illustrate the products and equipment discussed. Because of printing restrictions, the colors in map illustrations may vary from those in the original publication. The appendixes include substantial material which also should be of interest. In addition a glossary and an index are included to provide easy and quick access to the terms and concepts used in the text. For those interested in more technical detail than is provided in this handbook, the "Selected references" will be useful. Also, the publications of the professional societies listed in appendix 4 will provide technical information in detail.

  3. Geochemical characteristics and origin of the Lebowa Granite Suite, Bushveld Complex

    Science.gov (United States)

    Hill, M.; Barker, F.; Hunter, D.; Knight, R.

    1996-01-01

    The ??? 2052-Ma Lebowa Granite Suite (LGS) represents the culminating phase of an Early Proterozoic magmatic cycle in the Central Transvaal area of the Kaapvaal Province. Following extrusion of at least 200,000 km3 of intermediate to acid volcanics (Rooiberg Felsite), mafic and ultramafic magmas intruded at 2065 Ma to form the Rustenburg Layered Suite (RLS). The LGS includes the Nebo, Makhutso, Bobbejaankop, Lease, and Klipkloof granites. The Nebo Granite intruded the Rooiberg Felsite as sheets up to 4 km thick above the RLS. Smaller stocks of the other granites crosscut the Nebo. We determined major- and trace-element compositions and oxygen, Rb-Sr, and Sm-Nd isotope ratios for samples of: Nebo Granite; Rooiberg Felsite; granophyre and granophyric granite; Makhutso, Bobbejaankop, and Lease granites; and feldspar porphyry from areas throughout the exposed area of the LGS (Dennilton, Verena Balmoral, Enkeldoorn, Sekhukhune Plateau, Zaaiplaats-Potgeitersrus, and Western Transvaal). Coherent floor-to-roof geochemical trends exist in some areas, although it is not possible to model them convincingly. Regional variations in geochemistry exist and likely are related to source variations in the estimated 200,000 km3 of the Nebo Granite sheets. ??18O for the LGS range from +5.9??? to +9.5???; if these are approximate primary magmatic values, pelitic sediments cannot have been an important source for the LGS. The Rb-Sr isotope system has been altered, a finding consistent with previous studies. A mineral isochron for Nebo Granite near Dennilton yields a York regression age of 1995 ?? 99 Ma, with initial 143Nd/144Nd = 0.50978??8 and ???CHUR=-5.12. Samples from the Sekhukhune Plateau have higher 143Nd/144Nd ratios than do Dennilton-area samples, suggesting that the former originated from older or less LREE-enriched sources. We suggest that intrusion of mafic to ultramafic magmas at depth in the continental crust triggered melting of Archean quartzofeldspathic crystalline

  4. Study on Sr-Nd isotopes of mesozoic-cenozoic granites in Qinghai-Tibetan plateau

    International Nuclear Information System (INIS)

    Qiu Ruizhao; Deng Jinfu; Zhou Su; Xiao Qinghui; Cai Zhiyong

    2003-01-01

    Mesozoic-Cenozoic magmatic activities were intensive in Qinghai-Tibetan plateau. Nd-Sr isotopic compositions of representative granitic plutons in western Qinghai-Tibetan plateau are reported in this paper. Combining with past isotopic data, which has reported in eastern Qinghai-Tibetan plateau, Sr-Nd isotopic compositions and material source and genesis of Mesozoic and Cenozoic granites in Qinghai-Tibetan plateau have been studied. The research result indicates there are three types of granite existing in Qinghai-Tibetan plateau, the granites of Late stage of Yanshan Period which distributing on north and south boundary of Gandes block (namely in north and south granitic belts of Dangdes) and cause of oceanic crust subduction, have ( 87 Sr/ 86 Sr)i of 0.7041-0.7064, ε (Nd) t of +2.5 - +5.7 and TDM age of 312-562 Ma, positive ε Nd, low ( 87 Sr/ 86 Sr)i ratio and young Nd model ages suggest relatively high contents of mantle-derived components in their sources, and this type granite might melt from subduction oceanic crust. The granites occurred intra-Gangdes block which were caused by collision of continent and post-collision, have ( 87 Sr/ 86 Sr)i of 0.706-0.719, ε (Nd) t of -5.3 - -8.3 and TDM age of 1323-1496 Ma, negative ε Nd, relative high ( 87 Sr/ 86 Sr)i ratio with an mid-Proterozoic Nd model ages, suggest granite has the mixing genesis of mantle-derived components and old crustal components in their sources. With relatively small variation range in ε (Nd) t and TDM age, it might imply granitic isotopic source in Gandes block to keep relative homogenization in long period. The granites in Himalayan block which there is not oceanic material to join in melting and to cause of intra-continental subduction, has most ( 87 Sr/ 86 Sr)i ratio more than 0.720, ε (Nd) t of -10.3 - -16.3 and TDM age of 1792-2206 Ma, high ( 87 Sr/ 86 Sr)i ratio, low negative ε (Nd)t with old Nd isotopic model ages and consistent with the Sr, Nd isotopic compositions of basement

  5. Rapakivi Granite: An architectural emblem of St Petersburg and its utilisation in other world cities

    Science.gov (United States)

    Bulakh, Andrey; Gavrilenko, Vladimir; Panova, Helen

    2015-04-01

    The wide-ranging utilisation of Rapakivi Granite in St Petersburg is typified by the the famous Alexander Column, and 114 stone columns of St Isaac's Cathedralas well as the pedestal of the Nicholas I monument, and portals and basements of buildings of the Admiralty, General Staff, Senate and Synod. The stone is also frequently seen among pavement slabs and in parapets of embankments and bridges around the city. This list of examples where Rapakivi Granite has been used could be expanded further. All Rapakivi Granites used in the buildings of St.Petersburg were quarried from the so-called Vyborg massif. At present it has been found that the massif occupies an area of about 18 000 km2. In the past granite of the Vyborg massif was worked from several quarries in the vicinity of Fredrikshamn (Hamina) in Finland for use in St Peterburg. The best known granite quarries are at Piterlaks (Piuterlahti) and Gimmekyul (Hämeenkylä). Sometimes Rapakivi Granite form Finland differs in appearance from typical varieties. Thus columns of a classical portal in the house at N 7 in Pochtamtskaya Street are hewn from this greyish variety. Other examples are the plinth of the General Staff and Trade Store buildings. After the 1960s varieties from the Leningrad district, and Korosten (Ukraine) massifs were used in St Petersburg. Today it is possible to find examples of Rapakivi Granite from Finland in cities in the USA, South Africa, United Kingdom and Germany. It is a long used stone as demonstrated by its cultural heritage. It is also used as an ornamental or decorative stone in modern architecture. References: 1) Bulakh, A.G., Abakumova, N.B., and Romanovsky, J.V. St Petersburg: a History in Stone. 2010. Print House of St Petersburg State University. 173 p. (In English). 2) Tutakova, A.Ya., Romanovskiy, A.Z., Bulakh, A.G., and Leer, V.I. Dimension Stone of the Leningrad Region. Granites of the Karelia Isthmus in Architecture of the Modern St Petersburg. 2011. St Petersburg. 78 p

  6. Biotite stability in peraluminous granitic melts: Compositional dependence and application to the generation of two-mica granites in the South Bohemian batholith (Bohemian Massif, Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    René, Miloš; Holtz, F.; Cherhui, L.; Beermann, O.; Stelling, J.

    2008-01-01

    Roč. 102, 3-4 (2008), s. 538-553 ISSN 0024-4937 R&D Projects: GA MŠk(CZ) ME 555 Institutional research plan: CEZ:AV0Z30460519 Keywords : S-type granite * experiments * biotite stability Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.303, year: 2008

  7. [Analysis of X-ray fluorescence spectroscopy and plasma mass spectrometry of the Guidong granite body and its implications to granite evolution].

    Science.gov (United States)

    Li, Hong-Wei; Chen, Guo-Neng; Peng, Zhuo-Lun

    2013-07-01

    The Guidong composite granite body (CGB) located in the north Guangdong Province consists of numerous rock bodies formed respectively in the early and late Jurassic and early Cretaceous. Analysis of the granites of different period with X-ray fluorescence spectroscopy and plasma mass spectrometry indicates: (1) From the top of a granite body downwards, the felsic components of rock decrease, while the mafic and sigmaREE, LREE/HREE, (La/Yb)N, as well as delta Eu value increase, suggesting the material differentiation in the in-situ melting of crustal rocks and crystallisation of magma; (2) From old to young of the different period granite-massifs in the Guidong CGB, the felsic compositions totally decrease, and the mafic components, sigmaEE, LREE/HREE, (La/Yb)N, and delta Eu value increase as well, implying multiple crustal melting (remelting) events in the Mesozoic in this area; and (3) Primitive mantle-normalized spider diagram for trace elements of Guidong CGB suggests high maturity of the crust involved in the in-situ melting.

  8. Coastal California Digital Imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This digital ortho-imagery dataset is a survey of coastal California. The project area consists of approximately 3774 square miles. The project design of the digital...

  9. Coastal Harbors Modeling Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Coastal Harbors Modeling Facility is used to aid in the planning of harbor development and in the design and layout of breakwaters, absorbers, etc.. The goal is...

  10. Lithium and boron in late-orogenic granites - Isotopic fingerprints for the source of crustal melts?

    Science.gov (United States)

    Romer, Rolf L.; Meixner, Anette; Förster, Hans-Jürgen

    2014-04-01

    Geochemically diverse late- and post-Variscan granites of the Erzgebirge-Vogtland, the Saxon Granulite Massif, and Thuringia (Germany) formed by anatectic melting of Palaeozoic sedimentary successions and associated mafic to felsic volcanic rocks. The compositional diversity of the least evolved of these granites is largely inherited from the protoliths. We present Li and B-isotopic data of these granites and compare them with the isotopic composition of their protoliths, to investigate whether (i) there exist systematic differences in the Li and B-isotopic composition among different granite types and (ii) Li and B-isotopic compositions provide information on the granite sources complementary to information from the isotopic composition of Sr, Nd, and Pb and the trace-element signatures. Low-F biotite and two-mica granite types have flat upper continental crust (UCC)-normalized trace-element pattern with variable enrichments in Li, Rb, Cs, Sn, and W and depletions in Sr, Ba, and Eu. These signatures are least pronounced for the Niederbobritzsch biotite granite, which has the largest contribution of mafic material, and most pronounced for the two-mica granites. The granites show a relatively narrow range of δ7Li values (-3.0 to -0.5) and a broad range of δ11B values (-13.4 to +20.1). The δ11B values are lower in rocks with distinctly higher contents of Li, Rb, Cs, and Sn. The high δ11B of the Niederbobritzsch granite may be explained by the melting of former altered oceanic crust in its source. Relative to UCC, intermediate-F to high-F low-P granites show strong depletions in Sr, Ba, Eu as well as Zr and Hf, strong enrichments in Li, Rb, and Cs as well as Nb, Sn, Ta, and W, and REE pattern with stronger enrichments for HREE than for LREE. These granites show narrow ranges of δ7Li (-2.0 to +1.6) and δ11B values (-14.7 to -9.1), reflecting the smaller variability of the Li and B-isotopic composition in their source lithologies. The anomalously high δ7Li value

  11. Radon emanation during compression, fracturing and heating of granites

    Science.gov (United States)

    Pili, E.; Nicolas, A.; Girault, F.; Schubnel, A.; Fortin, J.; Passelègue, F. X.; Richon, P.

    2013-12-01

    Radon emanation during compression, fracturing and heating of granites É. Pili1,2, A. Nicolas3, F. Girault3, A. Schubnel3, J. Fortin3, F. Passelègue3, P. Richon1 1CEA, DAM, DIF, F-91297 Arpajon, France 2Institut de Physique du Globe, Sorbonne Paris Cité, 1 rue Jussieu, F-75005 Paris, France 3Ecole Normale Supérieure, 24 rue Lhomond, F-75005 Paris, France Precursory radon emissions have been reported previously in various seismically active areas. Nevertheless such observations, only partially understood, are the subject of much skepticism. Radon-222 is a radioactive gas, daughter of radium-226 from alpha-decay in the uranium-238 decay chain that is naturally present in rocks and soils. Its escape is facilitated by preferential pathways such as fractures. Its half-life is 3.8 days only. As a consequence, radon may accumulate during short period only, and is thought to be released prior, during and after earthquakes as stress is discharged and new fluid pathways are made available. However, the physical processes involved in radon emanation during stress variations remain mostly unknown in the field and poorly studied in the laboratory. Here, we investigate radon emanation from various granite samples: Isla Craig, Westerly, La Peyratte and various leucogranites. Radon emanation and diffusion length, measured first on intact samples, are compared with measurements performed after heating at 850°C. Despite extensive thermal fracturing, radon emanation decreases irreversibly after heating compared to intact sample, and the higher the heating temperature the smaller the radon emanation. This is explained by the disappearance of water-film at grain boundaries, which plays an important role in radon percolation through the porous space, and then, at higher temperatures, by dehydration and melting of biotites where radium is concentrated. The recoil range of radon is likely shorter in melted biotites than in intact ones. The effect of mechanical fracturing on radon

  12. Jurassic high heat production granites associated with the Weddell Sea rift system, Antarctica

    Science.gov (United States)

    Leat, Philip T.; Jordan, Tom A.; Flowerdew, Michael J.; Riley, Teal R.; Ferraccioli, Fausto; Whitehouse, Martin J.

    2018-01-01

    The distribution of heat flow in Antarctic continental crust is critical to understanding continental tectonics, ice sheet growth and subglacial hydrology. We identify a group of High Heat Production granites, intruded into upper crustal Palaeozoic metasedimentary sequences, which may contribute to locally high heat flow beneath the West Antarctic Ice Sheet. Four of the granite plutons are exposed above ice sheet level at Pagano Nunatak, Pirrit Hills, Nash Hills and Whitmore Mountains. A new Usbnd Pb zircon age from Pirrit Hills of 178.0 ± 3.5 Ma confirms earlier Rbsbnd Sr and Usbnd Pb dating and that the granites were emplaced approximately coincident with the first stage of Gondwana break-up and the developing Weddell rift, and 5 m.y. after eruption of the Karoo-Ferrar large igneous province. Aerogeophysical data indicate that the plutons are distributed unevenly over 40,000 km2 with one intruded into the transtensional Pagano Shear Zone, while the others were emplaced within the more stable Ellsworth-Whitmore mountains continental block. The granites are weakly peraluminous A-types and have Th and U abundances up to 60.7 and 28.6 ppm respectively. Measured heat production of the granite samples is 2.96-9.06 μW/m3 (mean 5.35 W/m3), significantly higher than average upper continental crust and contemporaneous silicic rocks in the Antarctic Peninsula. Heat flow associated with the granite intrusions is predicted to be in the range 70-95 mW/m2 depending on the thickness of the high heat production granite layer and the regional heat flow value. Analysis of detrital zircon compositions and ages indicates that the high Th and U abundances are related to enrichment of the lower-mid crust that dates back to 200-299 Ma at the time of the formation of the Gondwanide fold belt and its post-orogenic collapse and extension.

  13. Magnetic fabric, shape preferred orientation and regional strain in granitic rocks

    Science.gov (United States)

    Sen, Koushik; Mamtani, Manish A.

    2006-10-01

    Since granites do not preserve easily mappable foliations, lineations, and strain markers, determining the degree of shape preferred orientation (SPO) in them is challenging. The aim of this paper is to present a methodology for determining variation in the degree of SPO in granites and to test the feasibility of correlating the same with regional strain. The case of the Godhra Granite located in the southern parts of Aravalli Mountain Belt (India) is taken as an example. Degree of SPO is determined using two different techniques (a) anisotropy of magnetic susceptibility (AMS) and (b) strength of mineral lineation determined by calculating the concentration parameter ( κ) of von Mises distribution by digital image analysis of biotite ( κbi) and feldspar ( κf) in thin sections prepared parallel to the magnetic foliation plane. SPO data obtained using the above two techniques from 20 samples distributed across the entire granite are analysed. Samples with a higher κ also have a stronger magnetic fabric (magnetic lineation, L and degree of magnetic anisotropy P'). Also, the degree of SPO is greater for granites from the southern parts as compared to the northern parts. It is argued that this variation in degree of SPO cannot be attributed to rheological differences or strain resulting from difference in aspect ratios. Regional strain is inferred as the dominant factor. Since the emplacement of the Godhra Granite is synchronous with the tectonic rejuvenation along the Central Indian Tectonic Zone (CITZ) that lies to its south, the higher degree of SPO in the southern parts is attributed to its proximity to the CITZ. Whilst caution needs to be exercised to directly apply magnetic data as a measure of strain-intensity on a regional scale, it can be a useful guide to select samples for detailed SPO analysis using some alternative technique, especially for granites and other magmatic rocks that are devoid of mesoscopic strain markers.

  14. Granite disposal of U.S. high-level radioactive waste.

    Energy Technology Data Exchange (ETDEWEB)

    Freeze, Geoffrey A.; Mariner, Paul E.; Lee, Joon H.; Hardin, Ernest L.; Goldstein, Barry; Hansen, Francis D.; Price, Ronald H.; Lord, Anna Snider

    2011-08-01

    This report evaluates the feasibility of disposing U.S. high-level radioactive waste in granite several hundred meters below the surface of the earth. The U.S. has many granite formations with positive attributes for permanent disposal. Similar crystalline formations have been extensively studied by international programs, two of which, in Sweden and Finland, are the host rocks of submitted or imminent repository license applications. This report is enabled by the advanced work of the international community to establish functional and operational requirements for disposal of a range of waste forms in granite media. In this report we develop scoping performance analyses, based on the applicable features, events, and processes (FEPs) identified by international investigators, to support generic conclusions regarding post-closure safety. Unlike the safety analyses for disposal in salt, shale/clay, or deep boreholes, the safety analysis for a mined granite repository depends largely on waste package preservation. In crystalline rock, waste packages are preserved by the high mechanical stability of the excavations, the diffusive barrier of the buffer, and favorable chemical conditions. The buffer is preserved by low groundwater fluxes, favorable chemical conditions, backfill, and the rigid confines of the host rock. An added advantage of a mined granite repository is that waste packages would be fairly easy to retrieve, should retrievability be an important objective. The results of the safety analyses performed in this study are consistent with the results of comprehensive safety assessments performed for sites in Sweden, Finland, and Canada. They indicate that a granite repository would satisfy established safety criteria and suggest that a small number of FEPs would largely control the release and transport of radionuclides. In the event the U.S. decides to pursue a potential repository in granite, a detailed evaluation of these FEPs would be needed to inform site

  15. Petrogenesis of Karamaili alkaline A-type granites from East Junggar, Xinjiang (NW China) and their relationship with tin mineralization

    International Nuclear Information System (INIS)

    Su Yuping; Tang Hongfeng; Liu Congqiang; Hou Guangshun; Cong Feng; Sylvester, Paul J.; Qu Wenjun

    2007-01-01

    Several types of granites including alkaline granites and alkali feldspar granites are distributed in the Karamaili tectonic belt of East Junggar, Xinjiang, China. Some medium-small tin deposits are located within or near the contact zones of the granitic intrusions. The alkaline granites share all the features commonly observed in peralkaline A-type granites. They contain alkalic mafic minerals such as riebeckite and aegirine; have high contents of SiO 2 , alkalis, Rb, Th, Zr, Hf, REE (except Eu), and high ratios of FeO/MgO and Ga/Al; and show strong depletions in Ba, Sr, Eu in the spidergrams. Laser ablation-ICPMS U-Pb zircon geochronology indicates a crystallization age of ca. 305 Ma for the granites; TIMS analyses of the granites found high ε Nd (T) values of +5.9 to +6.5. Considering their geochemical features, alkaline granites most likely formed by fractional crystallization of graodioritic magmas, which were probably produced by partial melting of lower crustal basaltic to andesitic rocks formed from oceanic crustal materials that were deeply buried during late Palezoic subduction and accretion. Six molybdenite samples from the Sareshike tin deposit in East Junggar yielded an isochron age of 307±11 Ma (2σ) and a weighted mean model age of 306.5±3.4 Ma, consistent with zircon U-Pb ages of the alkaline granites. Low Re contents (0.323-0.961 ppm) in the molybdenite suggest that they originated from crustal sources related to the alkaline granites. Considering their identical ages, close spatial distribution, and similar sources, we argue that the A-type granites have a genetic relationship with the tin mineralization, and that the same association may be important elsewhere. (author)

  16. Groundwater chemistry of a nuclear waste reposoitory in granite bedrock

    International Nuclear Information System (INIS)

    Rydberg, J.

    1981-09-01

    This report concerns the prediction of the maximum dissolution rate for nuclear waste stored in the ground. That information is essential in judging the safety of a nuclear waste repository. With a limited groundwater flow, the maximum dissolution rate coincides with the maximum solubility. After considering the formation and composition of deep granite bedrock groundwater, the report discusses the maximum solubility in such groundwater of canister materials, matrix materials and waste elements. The parameters considered are pH, Eh and complex formation. The use of potential-pH (Pourbaix) diagrams is stressed; several appendixes are included to help in analyzing such diagrams. It is repeatedly found that desirable basic information on solution chemistry is lacking, and an international cooperative research effort is recommended. The report particularly stresses the lack of reliable data about complex formation and hydrolysis of the actinides. The Swedish Nuclear Fuel Safety (KBS) study has been used as a reference model. Notwithstanding the lack of reliable chemical data, particularly for the actinides and some fission products, a number of essential conclusions can be drawn about the waste handling model chosen by KBS. (1) Copper seems to be highly resistant to groundwater corrosion. (2) Lead and titanium are also resistant to groundwater, but inferior to copper. (3) Iron is not a suitable canister material. (4) Alumina (Al 2 O 3 ) is not a suitable canister material if groundwater pH goes up to or above 10. Alumina is superior to copper at pH < 9, if there is a risk of the groundwater becoming oxidizing. (5) The addition of vivianite (ferrous phosphate) to the clay backfill around the waste canisters improves the corrosion resistance of the metal canisters, and reduces the solubility of many important waste elements. This report does not treat the migration of dissolved species through the rock

  17. Alkali control of high-grade metamorphism and granitization

    Directory of Open Access Journals (Sweden)

    Oleg G. Safonov

    2014-09-01

    Full Text Available We review petrologic observations of reaction textures from high-grade rocks that suggest the passage of fluids with variable alkali activities. Development of these reaction textures is accompanied by regular compositional variations in plagioclase, pyroxenes, biotite, amphibole and garnet. The textures are interpreted in terms of exchange and net-transfer reactions controlled by the K and Na activities in the fluids. On the regional scale, these reactions operate in granitized, charnockitized, syenitized etc. shear zones within high-grade complexes. Thermodynamic calculations in simple chemical systems show that changes in mineral assemblages, including the transition from the hydrous to the anhydrous ones, may occur at constant pressure and temperature due only to variations in the H2O and the alkali activities. A simple procedure for estimating the activity of the two major alkali oxides, K2O and Na2O, is implemented in the TWQ software. Examples of calculations are presented for well-documented dehydration zones from South Africa, southern India, and Sri Lanka. The calculations have revealed two end-member regimes of alkalis during specific metamorphic processes: rock buffered, which is characteristic for the precursor rocks containing two feldspars, and fluid-buffered for the precursor rocks without K-feldspar. The observed reaction textures and the results of thermodynamic modeling are compared with the results of available experimental studies on the interaction of the alkali chloride and carbonate-bearing fluids with metamorphic rocks at mid-crustal conditions. The experiments show the complex effect of alkali activities in the fluid phase on the mineral assemblages. Both thermodynamic calculations and experiments closely reproduce paragenetic relations theoretically predicted by D.S. Korzhinskii in the 1940s.

  18. U-Pb ages and Nd isotope characteristics of the lateorogenic, migmatizing microcline granites in southwestern Finland

    Directory of Open Access Journals (Sweden)

    Matti Kurhila

    2005-01-01

    Full Text Available U-Pb ages and whole-rock Nd isotope data have been obtained from the Paleoproterozoic lateorogenic migmatizing microcline granites of southwestern Finland. Isotope dilution and ion microprobe U-Pb data on zircons and monazites show that the age spectrum of these granites is at least 1.85-1.82 Ga. Commonly, zircons and monazites record the same ages. The age variation in the Veikkola granite area is of the order of 25 Ma and indicates that this seemingly homogeneous granite consists of two separate intrusions. The zircons of the lateorogenic granites are pervasively altered and conventional U-Pb results are commonly discordant. The ion microprobe studies reveal that the granites contain very few inherited zircons with preserved original U-Pb isotope ratios, with the exception of the Oripää granite. Initial εNd values, mostly in the range of ‑0.5 to ‑1.0, imply a moderate input of older crustal material into most of the lateorogenic granites. A shift from more juvenile to less radiogenic Nd isotope composition is observed from north to south, and the variation pattern of εNd values of the lateorogenic granites is thus similar to that of the surrounding synorogenic granitoid rocks.

  19. Hydrothermal alteration and permeability changes in granitic intrusions related to Sn-W deposits : case study of Panasqueira (Portugal)

    Science.gov (United States)

    Launay, Gaetan; Sizaret, Stanislas; Guillou-Frottier, Laurent; Gloaguen, Eric; Melleton, Jérémie; Pichavant, Michel; Champallier, Rémi; Pinto, Filipe

    2017-04-01

    The Panasqueira Sn-W deposit occurs as a dense network of flat wolframite and cassiterite-bearing quartz veins concentrated in the vicinity of a hidden greisen cupola, and to a lesser extent as disseminated cassiterites in the greisen. Previous studies (Thadeu 1951; 1979) have suggested that the Panasqueira deposit is genetically related to magmatic activity for which the most part is unexposed, and being only represented by the greisen cupola. Hydrothermal fluid circulation during the final stages of granite crystallisation has probably led to the greisenisation of the cupola followed by the deposition of the mineralization in the veins system. Mineral replacement reactions that occurred during the greisenisation could affect rock properties (porosity, density and permeability) which control fluid circulation in the granite. This study aims to investigate effects of greisenisation reactions on the dynamic (time varying) permeability that ultimately leads to fluid circulation in the greisen cupola. To do so, petrological study and experimental determinations of hydrodynamic features (porosity and permeability) for different granite alteration levels and petrographic types (unaltered granite to greisen) are combined and then integrated in coupled numerical models of fluid circulation around the granitic intrusion. Greisen occurs in the apical part of the granitic body and results in the pervasive alteration of the granite along the granite-schist contact. This greisen consists mainly of quartz and muscovite formed by the replacement of feldspars and bleaching of biotites of the initial granite. Otherwise, greisen is generally vuggy which suggests a porosity increase of the granite during hydrothermal alteration processes. This porosity increase has a positive effect on the permeability of the granitic system. Indeed, experimental measurements of permeability with the Paterson press indicate that the initial granite is impermeable (10-20 m2) whereas the greisen is

  20. Smolt monitoring at the head of lower granite reservoir and lower Granite Dam, annual report 1999 operations.; ANNUAL

    International Nuclear Information System (INIS)

    United States. Bonneville Power Administration. Division of Fish and Wildlife; Idaho. Dept. of Fish and Game.

    2001-01-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon smolts O. nerka during the 1999 spring out-migration at migrant traps on the Snake River and Salmon River. All hatchery chinook salmon released above Lower Granite Dam were marked with a fin clip in 1999. Total annual hatchery chinook salmon catch at the Snake River trap was 440% of the 1998 number. The wild chinook catch was 603% of the previous year's catch. Hatchery steelhead trout catch was 93% of 1998 numbers. Wild steelhead trout catch was 68% of 1998 numbers. The Snake River trap collected 62 age-0 chinook salmon. During 1998 the Snake River trap captured 173 hatchery and 37 wild/natural sockeye salmon and 130 hatchery coho salmon O. kisutch. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with high flows. Trap operations began on March 14 and were terminated for the season due to high flows on May 25. The trap was out of operation for 18 d during the season due to high flow and debris. Hatchery chinook salmon catch at the Salmon River trap was 214%, and wild chinook salmon catch was 384% of 1998 numbers. The hatchery steelhead trout collection in 1999 was 210% of the 1998 numbers. Wild steelhead trout collection in 1999 was 203% of the 1998 catch. Trap operations began on March 14 and were terminated for the season due to high flows on May 21. The trap was out of operation for 17 d during the season due to high flow and debris

  1. Smolt monitoring at the head of Lower Granite Reservoir and Lower Granite Dam, annual report 1997 operations.; ANNUAL

    International Nuclear Information System (INIS)

    United States. Bonneville Power Administration. Division of Fish and Wildlife.

    1999-01-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha and steelhead trout O. mykiss smolts during the 1997 spring out-migration at migrant traps on the Snake River and Salmon River. All hatchery chinook salmon released above Lower Granite Dam were marked with a fin clip in 1997. Total annual hatchery chinook salmon catch at the Snake River trap was 49% of the 1996 number but only 6% of the 1995 catch. The wild chinook catch was 77% of the 1996 but was only 13% of 1995. Hatchery steelhead trout catch was 18% of 1996 numbers but only 7% of the 1995 numbers. Wild steelhead trout catch was 22% of 1996 but only 11% of the 1995 numbers. The Snake River trap collected eight age-0 chinook salmon and one sockeye/kokanee salmon O. nerka. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with high flows. Trap operations were terminated for the season due to high flows and trap damage on May 8 and were out of operation for 23 d due to high flow and debris. Hatchery chinook salmon catch at the Salmon River trap was 37% and wild chinook salmon catch was 60% of 1996 numbers but only 5% and 11% of 1995 catch, respectively. The 1997 hatchery steelhead trout collection was 13% of the 1996 catch and 32% of the 1995 numbers. Wild steelhead trout collection in 1997 was 21% of the 1996 catch and 13% of the 1995 numbers. Trap operations were terminated for the season due to high flows and trap damage on May 7 and were out of operation for 19 d due to high flow and debris

  2. Research of environmentally-friendly utilization methods of the crushed stone waste on granite quarries

    Directory of Open Access Journals (Sweden)

    Levytskyi V.G.

    2017-12-01

    Full Text Available The analysis of activity of stone-mining enterprises shows the low competitiveness of crushed stone products Upgrading the quality of crushed stone and production of the European standard fractions requires to use of new technologies and equipment. The main waste of crushed stone pits is сrushed granite waste, which high percent of an exit is caused by outdated equipment and incorrectly selected technological parameters of the crushing process. Crushed-granite waste is stored in dumps which occupy large areas and negatively effect on production area ecology. In November 2017, the Government of Ukraine accepted the National Waste Management Strategy until 2030, the main aim of it is develop a strategy of the mineral raw materials balanced use and international standards introduction at the national level. Therefore, the problem of complex utilization and recycling of waste from stone-mining enterprises with receiving a qualitative secondary product is relevant. The publication presents the сrushed granite waste volumes by crushed stone pit, its properties and main directions of utilization. The ecological influence of waste dumps, in particular granite dust, on the environment and human, the strategy of using non-waste technologies and ecological features of сrushed granite waste secondary processing are considered

  3. U-Pb ages in zircon of some classic granites from the Borborema province

    International Nuclear Information System (INIS)

    Neves, Benjamin Bley de Brito; Basei, Miguel Angelo Stipp; Passarelli, Claudia Regina; Santos, Edilton Jose dos

    2003-01-01

    The Neoproterozoic evolution of the Borborema Province in the east-northeast part of the South American platform exhibits remarkable, much studied granitic plutonism. In 1967 F. F. Almeida and co-workers discriminated a series of granitic typologies as 'Conceicao type', 'Itaporanga type' etc, mostly based upon general geological features and petrographic grounds. This preliminary classification has somehow been maintained in all subsequent papers up to now, despite all the newly observed plutons and the newly generated tectonic, geochemical and isotopic data since then. Samples of these classical types of granites from their type-localities were analyzed geo chronologically using the U-Pb method in zircons in response to the felt needs of the geological community, because previous age-determinations involved less accurate methods. The new data have been added to all other preexisting U-Pb data (from other granitic bodies) obtained over the last decade, making it possible to recognize three main stages of granitic magmatism for the Borborema Province: 650-625 Ma, 580-570 Ma and 545-520 Ma. The last group of dates is closely association with the escape tectonics of the Brasiliano-Pan African collage, which preceded the assembly of the super continental landmass of Western Gondwana. (author)

  4. Permeability of Granite Including Macro-Fracture Naturally Filled with Fine-Grained Minerals

    Science.gov (United States)

    Nara, Yoshitaka; Kato, Masaji; Niri, Ryuhei; Kohno, Masanori; Sato, Toshinori; Fukuda, Daisuke; Sato, Tsutomu; Takahashi, Manabu

    2017-11-01

    Information on the permeability of rock is essential for various geoengineering projects, such as geological disposal of radioactive wastes, hydrocarbon extraction, and natural hazard risk mitigation. It is especially important to investigate how fractures and pores influence the physical and transport properties of rock. Infiltration of groundwater through the damage zone fills fractures in granite with fine-grained minerals. However, the permeability of rock possessing a fracture naturally filled with fine-grained mineral grains has yet to be investigated. In this study, the permeabilities of granite samples, including a macro-fracture filled with clay and a mineral vein, are investigated. The permeability of granite with a fine-grained mineral vein agrees well with that of the intact sample, whereas the permeability of granite possessing a macro-fracture filled with clay is lower than that of the macro-fractured sample. The decrease in the permeability is due to the filling of fine-grained minerals and clay in the macro-fracture. It is concluded that the permeability of granite increases due to the existence of the fractures, but decreases upon filling them with fine-grained minerals.

  5. Evaluation of the effectiveness of laser crust removal on granites by means of hyperspectral imaging techniques

    Energy Technology Data Exchange (ETDEWEB)

    Pozo-Antonio, J.S., E-mail: santiago.pozo@udc.es [Laboratorio de Aplicacións Industriais do Láser, Centro de Investigacións Tecnolóxicas (CIT), Departamento de Enxeñaría Industrial II, Escola Politécnica Superior, Universidade de Coruña (UDC), Campus Ferrol, 15403 Ferrol (Spain); Fiorucci, M.P.; Ramil, A.; López, A.J. [Laboratorio de Aplicacións Industriais do Láser, Centro de Investigacións Tecnolóxicas (CIT), Departamento de Enxeñaría Industrial II, Escola Politécnica Superior, Universidade de Coruña (UDC), Campus Ferrol, 15403 Ferrol (Spain); Rivas, T. [Departamento de Enxeñaría dos Recursos Naturais e Medioambiente, Escola Superior de Minas, Universidade de Vigo, 36310 Vigo (Spain)

    2015-08-30

    Highlights: • Hyperspectral imaging techniques for determining the degree of crust removal on granites used in Cultural Heritage. • Hyperspectral imaging techniques allow to in situ evaluate of the effectiveness of the laser cleaning. • Hyperspectral imaging data are consistent with the information obtained by conventional techniques about the cleaning effectiveness. - Abstract: In this paper, we present a study of the application of the hyperspectral imaging technique in order to non-destructively evaluate the laser cleaning of the biogenic patina and the sulphated black crust developed on a fine-grained granite used in the construction of Cultural Heritage in NW Spain. The grained polymineral texture of the granite hinders the adjustment of laser irradiation parameters during the cleaning, and therefore the in situ process control. The cleaning was performed with a nanosecond pulsed Nd:YVO{sub 4} laser at 355 nm. A hyperspectral camera was used to in situ assess the effectiveness of cleaning by recording images of the rock surfaces before and during the laser treatment. Different analytical techniques were used to test the ability of the hyperspectral imaging technique to evaluate the cleaning process of the granite samples: optical microscopy, scanning electron microscopy with energy dispersive X-ray spectrometry (SEM - EDX), Fourier transform infrared spectroscopy (FTIR) and spectrophotometer colour measurements. The results indicated that hyperspectral imaging technique is a reliable and more affordable technique to in situ evaluate the process of laser cleaning of the biogenic patina and the sulphated black crust in fine-grained granites.

  6. Permeability of Granite Including Macro-Fracture Naturally Filled with Fine-Grained Minerals

    Science.gov (United States)

    Nara, Yoshitaka; Kato, Masaji; Niri, Ryuhei; Kohno, Masanori; Sato, Toshinori; Fukuda, Daisuke; Sato, Tsutomu; Takahashi, Manabu

    2018-03-01

    Information on the permeability of rock is essential for various geoengineering projects, such as geological disposal of radioactive wastes, hydrocarbon extraction, and natural hazard risk mitigation. It is especially important to investigate how fractures and pores influence the physical and transport properties of rock. Infiltration of groundwater through the damage zone fills fractures in granite with fine-grained minerals. However, the permeability of rock possessing a fracture naturally filled with fine-grained mineral grains has yet to be investigated. In this study, the permeabilities of granite samples, including a macro-fracture filled with clay and a mineral vein, are investigated. The permeability of granite with a fine-grained mineral vein agrees well with that of the intact sample, whereas the permeability of granite possessing a macro-fracture filled with clay is lower than that of the macro-fractured sample. The decrease in the permeability is due to the filling of fine-grained minerals and clay in the macro-fracture. It is concluded that the permeability of granite increases due to the existence of the fractures, but decreases upon filling them with fine-grained minerals.

  7. Petrogenesis of Mesozoic granites in the Xitian, South China: Evidence from whole-rock geochemistry and zircon isotopes

    Science.gov (United States)

    Liu, Q.; Sun, J.; He, M.; Hou, Q.; Niu, R.

    2017-12-01

    Mesozoic granitoids are widespread in southeastern China, which accompanied with lots of world-famous polymetallic deposits. The mineralization is believed to be related to the Mesozoic granitic magmatism. However, the petrogenesis of these granites and their relation to the mineralization are still debated. As a typical granitic pluton, Xitian granites from the eastern Hunan Province are formed during this period and associated with tungsten-tin deposit. Whole-rock geochemical, SIMS zircon geochronology and oxygen isotopes, as well as LA-ICPMS zircon Lu-Hf isotopic analyses, were carried out on a suite of rocks from Xitian granitic pluton to constrain their magmatic sources and petrogenesis. Xitian granitic pluton is mainly composed of biotite adamellite, biotite granite, fine-grained granite. SIMS and LA-ICPMS U-Pb dating of zircons indicate that there are two episodes of these rocks, i.e., Late Triassic granites (227-233Ma) and Late Jurassic granites (150-154Ma). The Xitian granites are silica-rich, potassic and weakly peraluminous. Petrographic and geochemical features show that they are highly fractionated I-type granites. The combined elemental and isotopic results indicated that the Late Triassic granite in Xitian area experienced a process of crystal fractionation of crustal-derived magmas coupled with strong assimilation of the surrounding rocks. The occurrence of Jurassic granitoids in Xitian area is attributed to ascending of mantle-derived magmas, which provide heat for partial melting of crustal materials. The Late Jurassic granite may be derived from juvenile crust or partial melting of ancient crustal rocks, whereas high degrees of crystal fractionation further enriched tungsten-tin in the evolved granitic rocks. This work was financially supported by the Research Cooperation between Institute and University of Chinese Academy of Sciences grant (Y552012Y00), Public Welfare Project of the Ministry of land and Resources of China (201211024

  8. Petrological and geochemical evolution of the Kymi stock, a topaz granite cupola within the Wiborg rapakivi batholith, Finland

    Science.gov (United States)

    Haapala, Ilmari; Lukkari, Sari

    2005-03-01

    The 6×3 km Kymi monzogranite stock represents the apical part of an epizonal late-stage pluton that was emplaced within the 1.65 to 1.63 Ga Wiborg rapakivi batholith. The stock has a well-developed zonal structure, from the rim to the center: stockscheider pegmatite, equigranular topaz granite, porphyritic topaz granite. The contact between the two granites is usually gradational within a few centimeters, but local inclusions of the porphyritic granite in the equigranular granite indicate that the latter solidified later. Hydrothermal greisen and quartz veins, some of which contain genthelvite, beryl, wolframite, cassiterite, and sulfides, cut the granites of the stock and the surrounding country rocks. The equigranular granite contains 1 to 4 vol.% topaz, and its biotite is lithian siderophyllite; the porphyritic granite has 0 to 3 vol.% topaz, and the mica is siderophyllite. The equigranular granite is geochemically highly evolved with elevated Li, Rb, Ga, Ta, and F, and very low Ba, Sr, Ti, and Zr. The REE patterns show deep negative Eu anomalies and tetrad effects indicating extreme magmatic fractionation and aqueous fluid-rock interaction. The zonal structure of the stock is interpreted as a result of differentiation within the magma chamber. Internal convection in the crystallizing magma chamber and upward flow of residual melt as a boundary layer along sloping contacts resulted in accumulation of a layer of highly evolved, volatile-rich magma in the apical part of the chamber. Crystallization of this apical magma produced the stockscheider pegmatite and the equigranular granite; the underlying crystal mush solidified as the porphyritic granite. Much of the crystallization took place from volatile-saturated melt, and episodic voluminous degassing expelled fluids into opened fractures where they or their derivatives reacted with country rocks and caused alteration and mineralization.

  9. Quantitative determination and monitoring of water distribution in Aespoe granite

    International Nuclear Information System (INIS)

    Zimmer, U.

    1998-01-01

    To identify possible zones of two-phase-flow and the extension of the excavation disturbed zone, geoelectric measurements are conducted in the ZEDEX- and the DEMO-tunnel. The electric resistivity of a hard rock is usually determined by its water content, its water salinity and its porosity structure. By calibration measurements of the resistivity on rocks with well known water content, a relation between resistivity and water content for Aespoe granite is determined. This relation is used to correlate the in-situ resistivity with the water content of the rock. To determine the in-situ resistivity between the ZEDEX- and the DEMO-tunnel an electrode array of nearly 300 electrodes was installed along the tunnel walls and in one borehole. With a semiautomatic recording unit which is operated by a telephone connection from the GRS-office in Braunschweig/Germany, the resistivity is monitored between and around the tunnels. To correlate the resistivity with the water content, the measured apparent resistivity has to be converted into a resistivity model of the underground. Since many thin water bearing fractures complicate this inversion process, the accuracy and resolution of the different inversion programs are checked before their application to the data. It was found that an acceptable quantitative reconstruction of the resistivity requires the integration of geometric information about the fracture zones into the inversion process. For a rough estimation of the position of possible fracture zones, a simple inversion without any geometric boundary conditions can be used. Since the maximum investigation area is limited along a single tunnel for profile measurements, tomographic measurements were also applied to estimate the resistivity distribution between the ZEDEX- and the DEMO-tunnel. These tomographic measurements have a lower resolution than the profile measurements due to the required large computer power, but result in reconstructions that give an estimate of

  10. Geochemical evolution of magmatism in Archean granite-greenstone terrains

    Science.gov (United States)

    Samsonov, A. V.; Larionova, Yu. O.

    2006-05-01

    Evolution of Archean magmatism is one of the key problems concerning the early formation stages of the Earth crust and biosphere, because that evolution exactly controlled variable concentrations of chemical elements in the World Ocean, which are important for metabolism. Geochemical evolution of magmatism between 3.5 and 2.7 Ga is considered based on database characterizing volcanic and intrusive rock complexes of granite-greenstone terrains (GGT) studied most comprehensively in the Karelian (2.9-2.7 Ga) and Kaapvaal (3.5-2.9 Ga) cratons and in the Pilbara block (3.5-2.9 Ga). Trends of magmatic geochemical evolution in the mentioned GGTs were similar in general. At the early stage of their development, tholeiitic magmas were considerably enriched in chalcophile and siderophile elements Fe2O3, MgO, Cr, Ni, Co, V, Cu, and Zn. At the next stage, calc-alkaline volcanics of greenstone belts and syntectonic TTG granitoids were enriched in lithophile elements Rb, Cs, Ba, Th, U, Pb, Nb, La, Sr, Be and others. Elevated concentrations of both the “crustal” and “mantle-derived” elements represented a distinctive feature of predominantly intrusive rocks of granitoid composition, which were characteristic of the terminal stage of continental crust formation in the GGTs, because older silicic rocks and lithospheric mantle were jointly involved into processes of magma generation. On the other hand, the GGTs different in age reveal specific trends in geochemical evolution of rock associations close in composition and geological position. First, the geochemical cycle of GGT evolution was of a longer duration in the Paleoarchean than in the Meso-and Neoarchean. Second, the Paleoarche an tholeiitic associations had higher concentrations of LREE and HFSE (Zr, Ti, Th, Nb, Ta, Hf) than their Meso-and Neoarchean counterparts. Third, the Y and Yb concentrations in Paleoarchean calc-alkaline rock associations are systematically higher than in Neoarchean rocks of the same type

  11. Durability of fired clay bricks containing granite powder

    Directory of Open Access Journals (Sweden)

    Xavier, G. C.

    2012-06-01

    Full Text Available Over the past few decades, hundreds of papers have been published on the benefits of including rock powder as a raw material in fired clay brick manufacture. Very little has been written, however, about the durability and long-term behaviour of the final product. As a rule, the ceramic bricks used in construction in developing countries are fired at low temperatures, which detracts from their mechanical performance. This is particularly visible in harsh environmental conditions, where weathering causes severe deterioration. The present paper describes the impact of weathering on clay bricks containing from 0 to 10% granite powder, an industrial by-product. The specimens were fired at 500, 700 or 900 ºC and subsequently exposed to natural environmental conditions or accelerated laboratory weathering. Their physical and mechanical properties were evaluated to determine the effect of the composition of raw materials on fired clay product durability.

    En las últimas décadas se han publicado cientos de artículos sobre las ventajas de incluir polvo de roca como materia prima en la fabricación de los ladrillos cerámicos. Sin embargo, la durabilidad y el comportamiento a largo plazo del producto final han sido objeto de pocas investigaciones. Por lo general, los ladrillos cerámicos empleados en la construcción en los países en vías de desarrollo se cuecen a temperaturas bajas, lo que impide el desarrollo de sus propiedades mecánicas. Esto queda especialmente patente cuando las condiciones ambientales son severas, en cuyo caso la meteorización puede provocar un deterioro importante. En este artículo se describe el efecto de la meteorización en ladrillos cerámicos que incorporaban entre un 0 y un 10% de polvo de granito, que es un derivado industrial. Las probetas se cocieron a 500, 700 o 900 °C y luego se sometieron a condiciones ambientales naturales o a un proceso de laboratorio de meteorización acelerada. Se evaluaron sus

  12. Microstructural variation of vitrified floor tile incorporated with granitic rock waste

    International Nuclear Information System (INIS)

    Souza, A.J.; Holanda, J.N.F.

    2009-01-01

    The ornamental rock industry from Northwest Fluminense generates huge amounts of wastes in the form of a fine powder. These wastes are deposited in nature without any care about environmental degradation, which can cause damage to public health, pollution of the natural water sources, and silted banks of rivers. In addition, they also can to affect the landscape aesthetically. In this work was used a granitic rock waste from Santo Antonio de Padua-RJ. This waste is rich in alkaline oxides, which promote the formation of liquid phase and assist the densification of traditional ceramics. The ceramic bodies with up to 47.5% granitic rock waste were pressed at 50 MPa. The ceramic pieces were fired at 1250 deg C. The evolution of sintered microstructure was evaluated by scanning electron microscopy and X-ray diffraction. The results showed that the granitic rock waste influences significantly the microstructure of the sintered ceramic bodies. (author)

  13. Seismogenic faulting in the Meruoca granite, NE Brazil, consistent with a local weak fracture zone.

    Science.gov (United States)

    Moura, Ana Catarina A; Oliveira, Paulo H S DE; Ferreira, Joaquim M; Bezerra, Francisco H R; Fuck, Reinhardt A; Nascimento, Aderson F DO

    2014-10-24

    A sequence of earthquakes occurred in 2008 in the Meruoca granitic pluton, located in the northwestern part of the Borborema Province, NE Brazil. A seismological study defined the seismic activity occurring along the seismically-defined Riacho Fundo fault, a 081° striking, 8 km deep structure. The objective of this study was to analyze the correlation between this seismic activity and geological structures in the Meruoca granite. We carried out geological mapping in the epicentral area, analyzed the mineralogy of fault rocks, and compared the seismically-defined Riacho Fundo fault with geological data. We concluded that the seismically-defined fault coincides with ∼E-W-striking faults observed at outcrop scale and a swarm of Mesozoic basalt dikes. We propose that seismicity reactivated brittle structures in the Meruoca granite. Our study highlights the importance of geological mapping and mineralogical analysis in order to establish the relationships between geological structures and seismicity at a given area.

  14. Comparative study of ornamental granite cleaning using femtosecond and nanosecond pulsed lasers

    Energy Technology Data Exchange (ETDEWEB)

    Rivas, T., E-mail: trivas@uvigo.es [Dpto. Ingeniería de los Recursos Naturales y Medioambiente. E.T.S. Ingeniería de Minas, Universidad de Vigo, 36200 Vigo Spain (Spain); Lopez, A.J.; Ramil, A. [Centro de Investigaciones Tecnológicas. Campus de Esteiro. Universidad de A Coruña 15403 Ferrol Spain (Spain); Pozo, S. [Dpto. Ingeniería de los Recursos Naturales y Medioambiente. E.T.S. Ingeniería de Minas, Universidad de Vigo, 36200 Vigo Spain (Spain); Fiorucci, M.P. [Centro de Investigaciones Tecnológicas. Campus de Esteiro. Universidad de A Coruña 15403 Ferrol Spain (Spain); Silanes, M.E. López de [Dpto. Ingeniería de los Recursos Naturales y Medioambiente. E.I. Forestales. Universidad de Vigo, Campus Pontevedra. 36005 Pontevedra Spain (Spain); García, A.; Aldana, J. R. Vazquez de; Romero, C.; Moreno, P. [Grupo de Investigación en Microprocesado de Materiales con Laser. Facultad de Ciencias, Universidad de Salamanca, 37008 Salamanca Spain (Spain)

    2013-08-01

    Granite has been widely used as a structural and ornamental element in public works and buildings. In damp climates it is almost permanently humid and its exterior surfaces are consequently biologically colonized and blackened We describe a comparative analysis of the performance of two different laser sources in removing biological crusts from granite surfaces: nanosecond Nd:YVO{sub 4} laser (355 nm) and femtosecond Ti:Sapphire laser at its fundamental wavelength (790 nm) and second harmonic (395 nm). The granite surface was analyzed using scanning electron microscopy, attenuated total reflection – Fourier transform infrared spectroscopy and profilometry, in order to assess the degree of cleaning and to characterize possible morphological and chemical changes caused by the laser sources.

  15. Comparative study of ornamental granite cleaning using femtosecond and nanosecond pulsed lasers

    International Nuclear Information System (INIS)

    Rivas, T.; Lopez, A.J.; Ramil, A.; Pozo, S.; Fiorucci, M.P.; Silanes, M.E. López de; García, A.; Aldana, J. R. Vazquez de; Romero, C.; Moreno, P.

    2013-01-01

    Granite has been widely used as a structural and ornamental element in public works and buildings. In damp climates it is almost permanently humid and its exterior surfaces are consequently biologically colonized and blackened We describe a comparative analysis of the performance of two different laser sources in removing biological crusts from granite surfaces: nanosecond Nd:YVO 4 laser (355 nm) and femtosecond Ti:Sapphire laser at its fundamental wavelength (790 nm) and second harmonic (395 nm). The granite surface was analyzed using scanning electron microscopy, attenuated total reflection – Fourier transform infrared spectroscopy and profilometry, in order to assess the degree of cleaning and to characterize possible morphological and chemical changes caused by the laser sources.

  16. Seismogenic faulting in the Meruoca granite, NE Brazil, consistent with a local weak fracture zone

    Directory of Open Access Journals (Sweden)

    ANA CATARINA A. MOURA

    2014-12-01

    Full Text Available A sequence of earthquakes occurred in 2008 in the Meruoca granitic pluton, located in the northwestern part of the Borborema Province, NE Brazil. A seismological study defined the seismic activity occurring along the seismically-defined Riacho Fundo fault, a 081° striking, 8 km deep structure. The objective of this study was to analyze the correlation between this seismic activity and geological structures in the Meruoca granite. We carried out geological mapping in the epicentral area, analyzed the mineralogy of fault rocks, and compared the seismically-defined Riacho Fundo fault with geological data. We concluded that the seismically-defined fault coincides with ∼E–W-striking faults observed at outcrop scale and a swarm of Mesozoic basalt dikes. We propose that seismicity reactivated brittle structures in the Meruoca granite. Our study highlights the importance of geological mapping and mineralogical analysis in order to establish the relationships between geological structures and seismicity at a given area.

  17. High radioactive heat-producing, economically potential granites around Jodhpur city, Malani Igneous Suite, Northwestern India

    International Nuclear Information System (INIS)

    Shrivastava, K.L.; Prajapat, Tina; Mathur, Anju; Gaur, Virendra; Dadhich; Mamta Chauhan, C.P.; Tripathi, Beena

    2013-01-01

    In the south and southeast periphery of the desert city of Jodhpur, there are pink and grey granite islands in the desert sand at Fitkasni-Rasida and Salawas-Nandanvan areas of Malani Igneous Suite (Neoproterozoic). We are reporting the average heat generation value of 15.33 HGU for first and 8.83 HGU for the second area that is much higher than the average (3.8 HGU) known for the continental crust. The concentration of uranium determined is two to four times higher than the average continental crust and thorium is still higher than U and K. The radioelement concentration (Ur) varies from 25.06 to 27 in the Salawas-Nandanvan granites and 43.73 to 75.81 in Fitkasni-Rasida granites. It clearly indicates a 'hot crust', hence favourable for the formation of mineralization of HFS elements, Nb, Ce, REE, U and Th, which need yet to be explored. (author)

  18. A Study on Tribological Behavior of Glass-Epoxy Composite Filled with Granite Dust

    Science.gov (United States)

    Ray, Subhrajit; Rout, Arun Ku; KuSahoo, Ashok

    2017-08-01

    Granite powder is one of the solid wastes generated from stone processing industry used as organic filler replacing the conventional ceramic fillers in polymer matrix composite to increase the mechanical properties. The present work investigates the addition of granite powder on erosion wear properties of epoxy-glass fiber composite. The solid particle erosion wear rates of these hybrid composites are recorded considering various control parameters as impingement angles, erodent sizes and impact velocities following erosion resistance test in an air erosion test device at room temperatures. The test was conducted as per the Taguchi experimental design to minimize the erosion loss of material. The SEM views show the surface resistivity for the granite added specimens. The microscopic study also indicates various methods of material removal, crater wear and other subjective allocation during erosion experiment of the samples.

  19. Effect of the state of internal boundaries on granite fracture nature under quasi-static compression

    Science.gov (United States)

    Damaskinskaya, E. E.; Panteleev, I. A.; Kadomtsev, A. G.; Naimark, O. B.

    2017-05-01

    Based on an analysis of the spatial distribution of hypocenters of acoustic emission signal sources and an analysis of the energy distributions of acoustic emission signals, the effect of the liquid phase and a weak electric field on the spatiotemporal nature of granite sample fracture is studied. Experiments on uniaxial compression of granite samples of natural moisture showed that the damage accumulation process is twostage: disperse accumulation of damages is followed by localized accumulation of damages in the formed macrofracture nucleus region. In energy distributions of acoustic emission signals, this transition is accompanied by a change in the distribution shape from exponential to power-law. Granite water saturation qualitatively changes the damage accumulation nature: the process is delocalized until macrofracture with the exponential energy distribution of acoustic emission signals. An exposure to a weak electric field results in a selective change in the damage accumulation nature in the sample volume.

  20. Petrochemistry and geochronology of pink granite from Songsak, East Garo Hills, Meghalaya

    International Nuclear Information System (INIS)

    Kumar, Sunil

    1990-01-01

    The pink granite of Songsak area, East Garo Hills district, Meghalaya, intrusive into Precambrian gneisses is inferred to be S-type, peraluminous, low calcium, post-kinematic granite. It is characterised by initial 87 Sr/ 86 Sr ratio of 0.728±.002, high K 2 O, high differentiation index and presence of normative corundum. The major mineral constituents are perthitic microcline, fresh interstitial microline, orthoclase with different degree of triclinisation, two generations of quartz and biotite. Sericitization of feldspars, presence of muscovite, rare chiastolite, fluorite and uraninite are other characteristics of the pink granites. Whole rock Rb-Sr dating assign an age of 500± 40 m.y. (author). 12 refs., 5 figs

  1. Conventional U-Pb dating versus SHRIMP of the Santa Barbara Granite Massif, Rondonia, Brazil

    Science.gov (United States)

    Sparrenberger, I.; Bettencourt, Jorge S.; Tosdal, R.M.; Wooden, J.L.

    2002-01-01

    The Santa Ba??rbara Granite Massif is part of the Younger Granites of Rondo??nia (998 - 974 Ma) and is included in the Rondo??nia Tin Province (SW Amazonian Craton). It comprises three highly fractionated metaluminous to peraluminous within-plate A-type granite units emplaced in older medium-grade metamorphic rocks. Sn-mineralization is closely associated with the late-stage unit. U-Pb monazite conventional dating of the early-stage Serra do Cicero facies and late-stage Serra Azul facies yielded ages of 993 ?? 5 Ma and 989 ?? 13 Ma, respectively. Conventional multigrain U-Pb isotope analyses of zircon demonstrate isotopic disturbance (discordance) and the preservation of inherited older zircons of several different ages and thus yield little about the ages of Sn-granite magmatism. SHRIMP U-Pb ages for the Santa Ba??rbara facies association yielded a 207Pb/206Pb weighted-mean age of 978 ?? 13 Ma. The textural complexity of the zircon crystals of the Santa Ba??rbara facies association, the variable concentrations of U, Th and Pb, as well as the mixed inheritance of zircon populations are major obstacles to using conventional multigrain U-Pb isotopic analyses. Sm-Nd model ages and ??Nd (T) values reveal anomalous isotopic data, attesting to the complex isotopic behaviour within these highly fractionated granites. Thus, SHRIMP U-Pb zircon and conventional U-Pb monazite dating methods are the most appropriate to constrain the crystallization age of the Sn-bearing granite systems in the Rondo??nia Tin Province.

  2. Petrochemical characteristics of Serra do Meio alkaline granite (Campo Alegre de Lourdes - Bahia State)

    International Nuclear Information System (INIS)

    Matos Maia Leite, C. de; Froes, R.J.B.

    1989-01-01

    The Serra do Meio granite outcrops near the town of Campo Alegre de Lourdes, north-northeast of Bahia State. The granite is intrusive into micachists, which are correlatives of the Salgueiro-Cachoeirinha Group (Early Proterozoic), during early to the syn-tectonic shear phase. The geological setting also comprises a phosphatic rock-bearing carbonatitic complex and gabbroid complexes with one of the main world resources of Fe-Ti-V. The granite mineralogical composition grades from Aegerine-augite alkali-feldspar granite/syenites to Leuco alcali-feldspar granite. The geochemical analysis shows SiO 2 -enrichment (67 to 76%), in alkalis (Na 2 +K 2 O, 7,5 to 12,5%), Nb (up to 680ppm), Zr (up to 2,390ppm), Y (up to 250ppm) e REE (up to 796ppm). The geochemical behaviour is peculiar to alkaline series, denoting a silica-oversaturated, potassium-rich, magma. The chondrite-normalized REE patterns display a first group with smooth slopes from the La to Lu, and a second one with negative slopes. Negative Eu anomalies are displayed in all the patterns. The first group is HREE-enriched, with low fractionation ratios. Samples with milonytic fabrics and higher fractionation ratios are related to the second group, suggesting the interaction of metassomatic fluids and the alkaline magma. Discriminant diagrams for Nb, Y and Rb, coupled with geophysical data, point to an intrusive granite in an extensional within a plate tectonic setting of attenuated continental crust. (author) [pt

  3. Characterization of the weathering of the Auriat granite (Creuse). Study of its porous space

    International Nuclear Information System (INIS)

    Leca, D.

    1990-05-01

    Our aim has been to characterize the alterations of the Auriat granite (Creuse - France) from a deep drilling. The two main parts of this memoir are : alterations prospecting and the analysis of the porous medium. After bibliographic review, we have characterized the Auriat granite and its alterations with classical methods: visual study, optical microscopy, MEB, Vickers micro-hardness, chemical analyses (scales of rock and grain), uniaxial compression and seismic velocities measurement in laboratory. We have defined alteration facies starting from the feldspar colors (rubefaction) that correspond to a physico-chemical reality. The second part of the memoir starts with the measurement of the granite porous volume. We have developed a technique adapted to the measurement of very low porosities (less than 2 %). The distribution of the porosities in relation with the facies shows that fresh granite has very low porosity (less than 1%) and weathered (rubefied) granite is slightly more porous (from about 0 to 2%). The decomposition of the global porosity in 'pore porosity' and 'crack porosity' shows that the fresh facies is affected by a set of open cracks. The rubefied facies presents widely clogged micro-cracks. We have taken up the mercury injection porosimetry test from the calculi used in the physic of high pressure. The study of porosimetry curves shows the existence of an infra-porosity (from 0.001 to 0.01 microns) for the rubefied facies. We have measured the gas permeability of the granite, then we have computed specific areas starting from porosity and permeability. Finally, we have presented a synthesis and the envisaged prospects. (author)

  4. Subsurface profiling of granite pluton using microtremor method: southern Aravalli, Gujarat, India

    Science.gov (United States)

    Joshi, Aditya U.; Sant, Dhananjay A.; Parvez, Imtiyaz A.; Rangarajan, Govindan; Limaye, Manoj A.; Mukherjee, Soumyajit; Charola, Mitesh J.; Bhatt, Meghnath N.; Mistry, Sagar P.

    2018-01-01

    We report, using the microtremor method, a subsurface granitic pluton underneath the Narukot Dome and in its western extension along a WNW profile, in proximity of eastern fringe of Cambay Rift, India. The dome and its extension is a part of the Champaner Group of rocks belonging to the Mesoproterozoic Aravalli Supergroup. The present finding elucidates development of an asymmetric double plunge along Narukot Dome. Microtremor measurements at 32 sites were carried out along the axial trace (N95°) of the dome. Fourier amplitude spectral studies were applied to obtain the ratio between the horizontal and vertical components of persisting Rayleigh waves as local ambient noise. Fundamental resonant frequencies with amplitude ≥1-sigma for each site are considered to distinguish rheological boundary. Two distinct rheological boundaries are identified based on frequency ranges determined in the terrain: (1) 0.2219-10.364 Hz recorded at 31 stations identified as the Champaner metasediment and granite boundary, and (2) 10.902-27.1119 Hz recorded at 22 stations identified as the phyllite and quartzite boundary. The proposed equation describing frequency-depth relationship between granite and overlaying regolith matches with those already published in the literature. The morphology of granite pluton highlights the rootless character of Champaner Group showing sharp discordance with granitic pluton. The findings of manifestation of pluton at a shallower depth imply a steep easterly plunge within the Champaner metasediments, whereas signature of pluton at a deeper level implies a gentle westerly plunge. The present method enables to assess how granite emplacement influences the surface structure.

  5. Radiation dose to workers due to the inhalation of dust during granite fabrication

    International Nuclear Information System (INIS)

    Zwack, L M; Stewart, J H; McCarthy, J F; Allen, J G; McCarthy, W B

    2014-01-01

    There has been very little research conducted to determine internal radiation doses resulting from worker exposure to ionising radiation in granite fabrication shops. To address this issue, we estimated the effective radiation dose of granite workers in US fabrication shops who were exposed to the maximum respirable dust and silica concentrations allowed under current US regulations, and also to concentrations reported in the literature. Radiation doses were calculated using standard methods developed by the International Commission on Radiological Protection. The calculated internal doses were very low, and below both US occupational standards (50 mSv yr −1 ) and limits applicable to the general public (1 mSv yr −1 ). Workers exposed to respirable granite dust concentrations at the US Occupational Safety and Health Administration (OSHA) respirable dust permissible exposure limit (PEL) of 5 mg m −3 over a full year had an estimated radiation dose of 0.062 mSv yr −1 . Workers exposed to respirable granite dust concentrations at the OSHA silica PEL and at the American Conference of Governmental Industrial Hygienists Threshold Limit Value for a full year had expected radiation doses of 0.007 mSv yr −1 and 0.002 mSv yr −1 , respectively. Using data from studies of respirable granite dust and silica concentrations measured in granite fabrication shops, we calculated median expected radiation doses that ranged from <0.001 to 0.101 mSv yr −1 . (paper)

  6. Southern Alaska Coastal Relief Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building coastal-relief models (CRM) for select U.S. coastal regions. Bathymetric, topographic, and shoreline data...

  7. Coastal Processes with Engineering Applications

    Science.gov (United States)

    Dean, Robert G.; Dalrymple, Robert A.

    2004-03-01

    The world's coastlines, dividing land from sea, are geological environments that are unique in their composition and the physical processes affecting them. At the dynamically active intersection of land and the oceans, humans have been building structures throughout history. Initially used for naval and commercial purposes, more recently recreation and tourism have increased activity in the coastal zone dramatically. Shoreline development is now causing a significant conflict with natural coastal processes. This text on coastal engineering will help the reader understand these coastal processes and develop strategies to cope effectively with shoreline erosion. The book is organized in four parts: (1) an overview of coastal engineering, using case studies to illustrate problems; (2) hydrodynamics of the coastal zone, reviewing storm surges, water waves, and low frequency motions within the nearshore and surf zone; (3) coastal responses including equilibrium beach profiles and sediment transport; (4) applications such as erosion mitigation, beach nourishment, coastal armoring, tidal inlets, and shoreline management.

  8. NATIONAL COASTAL CONDITION REPORT II

    Science.gov (United States)

    Coastal waters in the US include estuaries, coastalwetlands, coral reefs, mangrove and kep forests, seagrass meadows, and upwelling areas. Critical coastal habitats provide spawning grounds, nurseries, shelter, and food for finfish, shellfish, birds, and other wildlife. the nat...

  9. Diffusivity of Sr, I and Pu in Granite With Through-Diffusion Experiment

    DEFF Research Database (Denmark)

    Dang, Hai-Jun; Hou, Xiaolin; Liu, Wen-yuan

    2014-01-01

    The diffusion behavior of Sr, I and Pu in granite was investigated by through-diffusion experiment. the effective diffusion coefficients of Sr, I and Pu in granite at 26 °C were determined to be (1.24±0.03)×10-13 m2/s, (2.88±0.02)×10-13 m2/s and (1.33±0.52)×10-13 m2/s, respectively. It is also ob...

  10. Emplacement and deformation of the A-type Madeira granite (Amazonian Craton, Brazil)

    Science.gov (United States)

    Siachoque, Astrid; Salazar, Carlos Alejandro; Trindade, Ricardo

    2017-04-01

    The Madeira granite is one of the Paleoproterozoic (1.82 Ga) A-type granite intrusions in the Amazonian Craton. It is elongated in the NE-SW direction and is composed of four facies. Classical structural techniques and the anisotropy of magnetic susceptibility (AMS) method were applied to the study of its internal fabric. Magnetic susceptibility measurements, thermomagnetic curves, remanent coercivity spectra, optical microscopy and SEM (scanning electron microscopy) analyses were carried out on the earlier and later facies of the Madeira granite: the rapakivi granite (RG) and the albite granite (AG) respectively. The last one is subdivided into the border albite granite (BAG) and the core albite granite (CAG) subfacies. AMS fabric pattern is controlled by pure magnetite in all facies, despite significant amounts of hematite in the BAG subfacies. Microstructural observations show that in almost all sites, magnetic fabric correlates to magmatic state fabrics that are defined by a weak NE-SW orientation of mafic and felsic silicates. However, strain mechanisms in both subfacies of AG also exhibit evidence for solid-state deformation at high to moderate temperatures. Pegmatite dyke, strike slip fault (SFA-B-C), hydrothermal vein, normal fault (F1-2) and joint (J) structures were observed and their orientation and kinematics is consistent with the magmatic and solid-state structures. Dykes, SFA-C and F1, are usually orientated along the N70°E/40°N plane, which is nearly parallel to the strike of AMS and magmatic foliations. In contrast, veins, SFB, F2 and some J are oriented perpendicular to the N70°E trend. Kinematic analysis in these structures shows evidence for a dextral sense of movement in the system in the brittle regime. The coherent structural pattern for the three facies of Madeira granite suggests that the different facies form a nested pluton. The coherence in orientation and kinematics from magmatic to high-temperature solid-state, and into the brittle

  11. The natural analogous study of the migration of radionuclides in granite for nuclear waste disposal

    International Nuclear Information System (INIS)

    Yu Jinsheng

    1995-01-01

    Granite is one of the optimum types of surround rock for radioactive waste geological disposal. The study of natural analogues could provide very useful reference materials for selecting validating and designing site of repository in granite. The basic research substances are as follows: the fracture system and the circulation paths of the fluid, the hydrothermal alteration, the evolution of hydrothermal solution, the U, Th, REE element geochemical behaviours, the secondary mineral phases and its retention capacity for the concerned radioactive nuclides and the mass transfer modelling

  12. Age and Isotopic Studies of Some Pan-African Granite from North-Central Nigeria

    International Nuclear Information System (INIS)

    Breemen, O. van; Pidgeon, R.T.; Bowden, P.

    1977-01-01

    Twenty-nine Rb-Sr whole-rock isotopic analyses and three U-Pb zircon analyses on foliated granites and largely unfoliated charnockitic rocks indicate that the central part of the Pan-African belt in west Africa was characterised by intense orogenic plutonism. These data and Rb-Sr analyses on muscovite books from late cross-cutting pegmatites indicate that the peak of magmatic activity occurred 610 +- 10 m.y.ago. Initial 87 Sr/ 86 Sr ratios for the granitic and charnockitic rocks are in the range 0.7065-0.7125, and indicate a significantly older crustal component in the magmas

  13. General conceptual design study for a high-level radioactive waste repository in a granite formation

    International Nuclear Information System (INIS)

    1982-01-01

    The object of the general conceptual design study for a high level radioactive wastes repository in a deep lying granite formation is to ensure that technology available in 1980 is suitable for building, operating and finally closing such a repository. It is feasible to build and operate a 1000 m deep repository, located in a granite batholith, receiving 30000 AVM canisters (after 30 years surface cooling), the disposal rate being 1000 canisters per year. Cost of the operation amounts to 1,3% of the corresponding amount of electricity. The building, operating and final closing phases will take 81 years

  14. Analyses of SRS waste glass buried in granite in Sweden and salt in the United States

    International Nuclear Information System (INIS)

    Williams, J.P.; Wicks, G.G.; Clark, D.E.; Lodding, A.R.

    1991-01-01

    Simulated Savannah River Site (SRS) waste glass forms have been buried in the granite geology of the Stirpa mine in Sweden for two years. Analyses of glass surfaces provided a measure of the performance of the waste glasses as a function of time. Similar SRS waste glass compositions have also been buried in salt at the WIPP facility in Carlsbad, New Mexico for a similar time period. Analyses of the SRS waste glasses buried in-situ in granite will be presented and compared to the performance of these same compositions buried in salt at WIPP

  15. Geomorphometry in coastal morphodynamics

    Science.gov (United States)

    Guisado-Pintado, Emilia; Jackson, Derek

    2017-04-01

    Geomorphometry is a cross-cutting discipline that has interwoven itself into multiple research themes due to its ability to encompass topographic quantification on many fronts. Its operational focus is largely defined as the extraction of land-surface parameters and earth surface characterisation. In particular, the coastal sciences have been enriched by the use of digital terrain production techniques both on land and in the nearshore/marine area. Numerous examples exist in which the utilisation of field instrumentation (e.g. LIDAR, GPS, Terrestrial Laser Scanning, multi-beam echo-sounders) are used for surface sampling and development of Digital Terrain Models, monitoring topographic change and creation of nearshore bathymetry, and have become central elements in modern investigations of coastal morphodynamics. The coastal zone is a highly dynamic system that embraces variable and at times, inter-related environments (sand dunes, sandy beaches, shoreline and nearshore) all of which require accurate and integrated monitoring. Although coastal studies can be widely diverse (with interconnected links to other related disciplines such as geology or biology), the characterisation of the landforms (coastal geomorphology) and associated processes (morphodynamics, hydrodynamics, aeolian processes) is perhaps where geomorphometry (topo-bathymetry quantification) is best highlighted. In this respect, many tools have been developed (or improved upon) for the acquisition of topographic data that now commands a high degree of accuracy, simplicity, and ultimately acquisition cost reduction. We present a series of field data acquisitions examples that have produced land surface characterisation using a range of techniques including traditional GPS surveys to more recent Terrestrial Laser Scanning and airborne LIDAR. These have been conducted within beach and dune environments and have helped describe erosion and depositional processes driven by wind and wave energy (high

  16. U-Pb age in zircon of intrusive granite at Acopiara complex, Crystal region, domain Central Ceara, Brazil

    International Nuclear Information System (INIS)

    Neri, T.F.O.; Hamelak, G.M.S.; Azevedo, L.R.; Mattos, I.C.; Verissimo, C.U.V.; Nogueira Neto, J.A.; Lima, M.N.

    2015-01-01

    Granitic body mineralogically composed by two micas, located at Crystal region, Ceara Central domain and intruded into lithotypes from Acopiara complex, provided an age of ∼526 Ma, indicating important period of magma generation of granitic composition associated with crustal anatexia, during Paleozoic

  17. REE enrichment in granite-derived regolith deposits of the southeast United States: Prospective source rocks and accumulation processes

    Science.gov (United States)

    Foley, Nora K.; Ayuso, Robert A.; Simandl, G.J.; Neetz, M.

    2015-01-01

    The Southeastern United States contains numerous anorogenic, or A-type, granites, which constitute promising source rocks for REE-enriched ion adsorption clay deposits due to their inherently high concentrations of REE. These granites have undergone a long history of chemical weathering, resulting in thick granite-derived regoliths, akin to those of South China, which supply virtually all heavy REE and Y, and a significant portion of light REE to global markets. Detailed comparisons of granite regolith profiles formed on the Stewartsville and Striped Rock plutons, and the Robertson River batholith (Virginia) indicate that REE are mobile and can attain grades comparable to those of deposits currently mined in China. A REE-enriched parent, either A-type or I-type (highly fractionated igneous type) granite, is thought to be critical for generating the high concentrations of REE in regolith profiles. One prominent feature we recognize in many granites and mineralized regoliths is the tetrad behaviour displayed in REE chondrite-normalized patterns. Tetrad patterns in granite and regolith result from processes that promote the redistribution, enrichment, and fractionation of REE, such as late- to post- magmatic alteration of granite and silicate hydrolysis in the regolith. Thus, REE patterns showing tetrad effects may be a key for discriminating highly prospective source rocks and regoliths with potential for REE ion adsorption clay deposits.

  18. Calcite veins of the Stripa granite (Sweden) as records of the origin of the ground waters and their interactions with the granitic body

    International Nuclear Information System (INIS)

    Clauer, N.; Fritz, B.; Frape, S.K.

    1989-01-01

    A Sr isotopic study combined with stable isotope determinations (δ 18 O and δ 13 C), petrographic observations and speciation calculations suggests that the Stripa granite (Sweden) contains at least three different types of calcite veins. One type with δ 18 O = -18 to -24 per-thousand (PDB) and 87 Sr/ 86 Sr = 0.7814 to 1.0696 probably formed at temperatures above 200 degree C, together with chlorite and epidote, during one or two metamorphic events which are recorded in the Rb-Sr systematics of some minerals of the granite at 1.4 and 0.8 Ga. Another type with δ 18 O = -12 to -18 per-thousand (PDB) and 87 Sr/ 86 Sr = 0.7406 to 0.7536 and mainly associated with chlorite, is most likely in equilibrium with the present day ground waters, which probably have reacted with the fracture minerals of the granitic body for a long time without any supply of external fluids. The third type of calcite with δ 18 C = -12 to -18 per-thousand (PDB), δ 13 C = -5 to -45 per-thousand (PDB) and 87 Sr/ 86 Sr = 0.7266 to 0.7406, could have formed from reactions involving methane oxidation or sulfate reduction in the presence of bacteria

  19. ``Granite tectonics'' revisited: insights from comparison of K-feldspar shape-fabric, anisotropy of magnetic susceptibility (AMS), and brittle fractures in the Jizera granite, Bohemian Massif

    Science.gov (United States)

    Žák, Jiří; Verner, Kryštof; Klomínský, Josef; Chlupáčová, Marta

    2009-07-01

    In the Jizera granite of the Krkonoše-Jizera Plutonic Complex, northern Bohemian Massif, contrasting patterns of magmatic K-feldspar fabrics and brittle fractures characterize different structural levels of the pluton. The uppermost exposed level at ˜800-1,100 m above sea level is dominated by flat foliation that overprints two steep foliations. In contrast, K-feldspar shape-fabric in an underground tunnel (˜660 m above sea level) shows complex variations in orientation and intensity. Magnetic fabric carried by coaxial contributions of biotite, magnetite, and maghemite is homogeneous along the examined section of the tunnel, and is decoupled from the K-feldspar fabric. The Jizera granite is crosscut by two regional sets of subvertical fractures (˜NE-SW and ˜NW-SE) and by near-surface exfoliation joints. The multiple fabrics are inferred to reflect a complex magmatic strain history at different structural levels of the pluton, bearing little or no relationship to the fracture network. In contrast to the original concept of Hans Cloos (“granite tectonics”), we conclude that no simple genetic relationship exists between fabrics and fractures in plutons. An alternative classification of fractures in plutons thus should avoid relationships to magmatic fabrics and should instead consist of cooling, syntectonic, uplift, and post-uplift fractures.

  20. Biofouling of granite-rapakivi in St. Petersburg monuments and in the quarry in Russia and Finland

    Science.gov (United States)

    Vlasov, Dmitry; Panova, Elena; Alampieva, Elena; Olhovaya, Elena; Popova, Tatyana; Vlasov, Alexey; Zelenskaya, Marina

    2013-04-01

    Granite-rapakivi was widely used in the architecture of St. Petersburg: the facades of buildings, embankments of rivers and canals, bridges, sculptural monuments, pedestals, facing the metro stations. This stone is rapidly destroyed due to the peculiarities of its structure. Biofouling of granite is insufficiently studied. Cause the destruction of granite can be bacteria, microscopic algae, fungi, mosses, lichens, higher plants, invertebrates and vertebrates. They often form specific lithobiotic communities that contribute to the destruction of granite-rapakivi. The objects of research were monuments of St. Petersburg (granite sculpture, facades, facing embankments) as well as granite-rapakivi quarries in Russia and Finland, where the stone was quarried for use in St. Petersburg. Sampling was carried out from the most typical biofouling sites. Different methods were applied for the study of damaged granite: petrographic analysis, light and scanning electron microscopy, methods for detection and identification of microorganisms, X-ray microprobe analysis. As result the main forms of granite destruction were described: fractures, ovoid weathering, granular disintegration, surface films, crusts and layers, pitting and fouling. Lichens, mosses, herbaceous and micromycetes were dominated on the granite-rapakivi in quarries. For example, in a Monferran quarry (Virolahti region) the complicated lithobiotic community was revealed. It included 30 species of micromycetes, 31 species of lichens, 10 species of moss. Bacteriological analysis showed the dominance of bacteria Bacillus, and actinomycetes in microbial biofilms. More than 100 species of plants were found on the granite embankments in St. Petersburg. They were confined to the cracks, seams of granite blocks. Plants and mosses were common to the granite embankments of rivers and canals in the central (historical) part of the city. Dimensions of mosses depend on the area of the deepening which they occupy. The most

  1. Geological characteristics of granite type uranium deposits in middle of Inner Mongolia in comparison with south China

    International Nuclear Information System (INIS)

    Wang Gui

    2012-01-01

    Granites extensively distributed in middle of Inner Mongolia and South China, namely Caledonian, Hercynian and Yanshanian. Some of the intrusive are composed of granites which belong to different ages. Some of the uranium deposits were found inside the granite bodies or in sedimentary rocks and meta sedimentary rocks along the exocontact zone. Granite rock was comparing in middle Inner Mongolia and South China, including Uranium ore-forming geological conditions. ore-forming process and Ore-controlling factors. Think the Uranium ore-forming geological conditions is similar; ore-forming process is mainly for low-mid temperature hot liquid; Uranium ore bodies (uranium mineralization) was controlled by fracture. Explain granite type uranium mineralization potential is tremendous in middle of Inner Mongolia. (author)

  2. Generation of post-collisional normal calc-alkaline and adakitic granites in the Tongbai orogen, central China

    Science.gov (United States)

    Zhang, Wen-Xiang; Zhu, Liu-Qin; Wang, Hao; Wu, Yuan-Bao

    2018-01-01

    Post-collisional granites are generally generated by partial melting of continental crust during orogenic extension. The occurrence of normal calc-alkaline granites following adakitic granites in a collisional orogen is frequently supposed as a sign of tectonic regime transition from compression to extension, which has been debated yet. In this paper, we present a comprehensive study of zircon U-Pb ages, Hf-O isotopes, as well as whole-rock major and trace elements and Sr-Nd isotopes, for Tongbai and Jigongshan post-collisional granitic plutons in the Tongbai orogen. Zircon U-Pb dating yields intrusion ages of ca. 140 and 135 Ma for the Tongbai and Jigongshan plutons, respectively, suggesting they are post-collisional granites. These granites are high-K calc-alkaline series, metaluminous to weakly peraluminous with A/CNK ratios of 0.85-1.08. The Tongbai gneissic granites are normal calc-alkaline granite, having variable SiO2 (61.93-76.74 wt%) and Sr/Y (2.9-38.9) and (La/Yb)N (1.7-30.1) ratios with variably negative Eu anomalies (0.41-0.92). They have relatively high initial Sr isotope ratios of 0.707571 to 0.710317, and low εNd(t) (- 15.74 to - 11.09) and εHf(t) (- 17.6 to - 16.9) values. Their Nd and Hf model ages range from 2.2 to 1.8 Ga and 2.3 to 2.2 Ga. On the contrary, the Jigongshan granites show higher SiO2 (66.56-72.11 wt%) and Sr/Y (30.1-182.0) and (La/Yb)N (27.4-91.4) ratios with insignificant Eu anomalies (0.73-1.00), belonging to adakitic granite. They have Isr = 0.707843-0.708366, εNd(t) = - 19.83 to - 17.59, and εHf(t) = - 26.0 to - 23.5. Their Nd and Hf model ages vary from ca. 2.5 to 2.4 Ga and ca. 2.8 to 2.6 Ga. The Tongbai and Jigongshan granites are characterized by mantle-like zircon δ18O values (5.17-5.46‰). These geochemical features suggest that the Tongbai and Jigongshan granites were derived from partial melting of Paleoproterozoic and Archean continental crust, respectively. Fractional crystallization affected the geochemical

  3. Fluid paleocirculations at the cover/granite interface in the Rhine graben

    Science.gov (United States)

    Lerouge, Catherine; Dezayes, Chrystel; Bailly, Laurent; Flehoc, Christine; Guerrot, Catherine; Wille, Guillaume

    2017-04-01

    The Rhine Graben is a major site of development for the geothermal heating production in France. Targeted geothermal reservoirs are in deep Hercynian granitic basement which is fractured dominated system, and more recently at the cover/basement interface. In this framework of geothermal exploration, a better understanding of the hydraulic behaviour of the fracture network and fluid/rock interactions is needed. For that fracture fillings in Hercynian granitic basement and in the formations of the cover (Permian rhyolites, Permian and Triassic sediments) were studied for mineralogy, fluid inclusion microthermometry and (C, O, Sr) isotopes in order to trace paleocirculations at the cover/granite interface in the Rhine Graben. Data were acquired on fracture fillings in samples of the basement/cover interfaces from the EPS1 borehole at Soultz-sous-Forêt in the Rhine graben at 1417 meters depth, and from outcrops in quarries on the flanks of the graben (Waldhambach, Saint Pierre Bois, Windstein, Heidelberg). Mineral sequences of polyphased fillings were interpreted in relation with the geological context including late evolution of the Hercynian basement and major extensive tectonic events. Quartz, carbonates, sulfates and illite are major minerals identified in fractures crosscutting Hercynian granites, Permian rhyolite (Waldhambach) and Permian and Triassic sedimentary cover. Although quartz being considered as a major mineral filling fractures, petrological observations showed that carbonates are also an important and probably underestimated phase of filling, and of interest for two reasons. Firstly, from a geothermal point of view, they contribute to the clogging of fractures. Secondly, from a scientific point of view, they are informative on the variations of fluid chemistry through geological times. Among carbonates, dominant dolomite with minor ankerite, Mn-bearing carbonates and siderite was identified by CL, SEM and EPMA in fractures. A same generation of

  4. Hybridization in the subvolcanic Jaala-Iitti complex and its petrogenetic relation to rapakivi granites and associated mafic rocks of southeastern Finland

    OpenAIRE

    Salonsaari, P.T.

    1995-01-01

    The 1630 Ma Jaala-Iitti complex is an example of bimodal rapakivi granite magmatism in which the interaction of granite and diabase magmas have led locally to hybridization. The dyke-like complex is situated at the northwestern margin of the Wiborg rapakivi batholith in southeastern Finland, cutting both the Proterozoic Svecofennian metamorphic crust and the Wiborg batholith. The complex consists mainly of non-hybridized compositionally homogeneous granites, i.e., hornblende granite and hornb...

  5. Petrogenesis and tectonic setting of the Devonian Xiqin A-type granite in the northeastern Cathaysia Block, SE China

    Science.gov (United States)

    Cai, Da-wei; Tang, Yong; Zhang, Hui; Lv, Zheng-Hang; Liu, Yun-long

    2017-06-01

    Most Silurian-Devonian granites in South China are S- or I-type granites, which are suggested to be petrogenetically related to the Wuyi-Yunkai orogeny. In this paper, we present the detailed LA-ICP-MS zircon U-Pb dating, major and trace element geochemical, and Nd-Hf isotopic data for Xiqin A-type granites in the northeastern Cathaysia Block, SE China. Zircon U-Pb dating results show that the Xiqin granites were emplaced at about 410 Ma, indicating that they were generated at the end of Wuyi-Yunkai orogeny. These granites are high in K2O + Na2O (6.31-8.79 wt%), high field strength elements (Zr + Nb + Ce + Y = 427-699 ppm), rare earth elements (total REE = 221-361 ppm) as well as high Ga/Al ratios (10,000 Ga/Al = 2.50-3.10), and show characteristics typical of A-type granites. εHf(t) values of the Xiqin granites mainly vary from -0.4 to -3.1 and yield Mesoproterozoic T2DM(Hf) (mainly ranging from 1.29 to 1.45 Ga). The εNd(t) values are from -1.23 to -2.11 and T2DM(Nd) vary from 1.25 to 1.32 Ga. These isotopic data suggest that the Xiqin granites were generated by partial melting of metavolcanic rocks with minor metasedimentary rocks in the lower crust. Our data on the Xiqin granites, coupled with previous studies of Silurian-Devonian magmatism, suggest that the tectonic regime had changed to a strongly post-collisional extension environment in the Wuyi-Yunkai orogen at least since 410 Ma, and that delamination, which accounts for the change in stress from the compression to extension and asthenospheric upwelling during the early Paleozoic, plays a significant role in the generation of Xiqin A-type granites.

  6. Managing Coastal Pollution

    International Nuclear Information System (INIS)

    Quevenco, R.

    2010-01-01

    Concern over the growing incidence of pollution in the Caribbean has been on the rise, as it has the potential to affect livelihoods dependent on fishing and tourism. The IAEA's Department of Technical Cooperation launched a regional project on the use of nuclear techniques to address coastal management issues in the Caribbean.

  7. Scour around coastal structures

    DEFF Research Database (Denmark)

    Sumer, B. Mutlu; Whiteouse, J. S.; Tørum, A.

    2001-01-01

    This paper summarizes the results of the European Union Marine Science and Technology (EU MAST) III project "Scour Around Coastal Structures" (SCARCOST). The summary is presented under three headings: (1) Introduction; (2) Flow and scour processes with the subheadings: flow and scour processes...

  8. Pollution of Coastal Seas

    Indian Academy of Sciences (India)

    Pollution of various environments is a consequence of population growth and industrialisation. Coastal seas form part of marine environment and are very rich in minerals, crude oil, fishes etc. They are also being used for disposal of wastes from cities. Various types of wastes, if not properly treated, would cause serious ...

  9. Coping with Coastal Change

    NARCIS (Netherlands)

    Nichols, Robert J.; Stive, Marcel J.F.; Tol, Richard S.J.

    2015-01-01

    This chapter focuses on how to cope with coastal change and its implications. There are two major types of response: mitigation representing source control of drivers, such as greenhouse gas emissions and groundwater withdrawal, and adaptation referring to behavioral changes that range from

  10. Coastal hazards: hurricanes, tsunamis, coastal erosion

    Science.gov (United States)

    Vandas, Stephen; Mersfelder, Lynne; Farrar, Frank; France, Rigoberto Guardado; Yajimovich, Oscar Efraín González; Muñoz, Aurora R.; Rivera, María del C.

    1996-01-01

    Oceans are the largest geographic feature on the surface of the Earth, covering approximately 70% of the planet's surface. As a result, oceans have a tremendous impact on the Earth, its climate, and its inhabitants. The coast or shoreline is the boundary between ocean environments and land habitats. By the year 2025, it is estimated that approximately two-thirds of the world's population will be living within 200 kilometers of a coast. In many ways, we treat the coast just like any other type of land area, as a safe and stable place to live and play. However, coastal environments are dynamic, and they constantly change in response to natural processes and to human activities.

  11. Micromorphology of a weathered granite near the Ría de Arosa (NW Spain)

    NARCIS (Netherlands)

    Bisdom, E.B.A.

    1966-01-01

    A detailed study has been made of several weathering profiles on the late-Hercynian Caldas de Reyes granite, NW-Spain. The field examination has been complemented by laboratory studies of large thin sections of hardened weathered material in conjunction with X-ray diffraction analyses. Three groups

  12. Radiometric evaluation of granite tables in environment public in the city of Recife-PE, Brazil

    International Nuclear Information System (INIS)

    Rocha, Edilson A.; Amaral, Romilton dos S.; Santos Junior, Jose A. dos; Bezerra, Jairo D.

    2011-01-01

    Granite in Pernambuco has been used as raw-material in several utensils, amongst which, furniture and decoration objects. This granite, besides being traded internally, is also exported to Asia and Europe. Differentiated content of some radionuclides of the ( 238 U and 232 Th) and 40 K natural series above average content of other rocks is also commonly found, due to its origin and geological formation. The gamma radiation stems from the decay of the given series, followed by the 40 K, and it should not exceed the 1 mSv.y -1 limit per person of the public, according to the current radiological protection rules (ICRP, 60). This work aimed to radiometrically assess the granite tables used by the public of a well visited restaurant in the city of Recife. It is expected to contribute to the environmental monitoring and to assess the possible health risks for humans. The tables were monitored for a period of about one year. Dosimetric tablets of CaSO 4 :Dy were used. The findings showed doses ranges from the background to 4.7 mSv.y -1 , with general average of dose rate equal to 3.0 mSv.y -1 . Therefore, it was concluded that despite the average dose rates in the different granite objects studied being higher than the recommended rate, the exposure does not offer risks to their users, due to the contact time (meal time) and the levels of radioactive emission found. (author)

  13. Impact of Granite Quarrying on the Health of Workers and Nearby ...

    African Journals Online (AJOL)

    Impact of Granite Quarrying on the Health of Workers and Nearby Residents in Abeokuta Ogun State, Nigeria. ... Suspended Particulate Matter (SPM) meter was employed to monitor the level of particulate matter (PM10) within and around five quarry sites selected for this study. The data collected from hospital records of ...

  14. On the interaction of granite with Tc(IV) and Tc(VII) in aqueous solution

    International Nuclear Information System (INIS)

    Eriksen, T.E.; Cui, Daquing

    1991-10-01

    The behaviour of technetium in granite-groundwater systems under reducing conditions was investigated. The anion TcO 4 - was reduced to Tc(IV) and simultaneously precipitated as TcO 2 xnH 2 O on the granite surfaces. The electron sources are assumed to be iron oxides and/or iron containing minerals in the granite. The technetium concentration in ground water under repository conditions may be predicted assuming TcO 2 xnH 2 O as the solid phase and TcO(OH) 2 0 and TcO 4 - as the predominant aqueous complexes using a formation constant for TcO(OH) 2 0 of log K = -8.16 and a standard reduction potential E 0 for the reaction TcO 4 - + 3e - + 4H + = TcO 2 xnH 2 O of 0.738 V. The surface related distribution ratio K a for TcO(OH) 2 0 between Stripa granite and ground water is approximately 1 cm based on geometrical surface area. (au)

  15. Muskovit-biotitický granit z Kalvárie v Jihlavě

    Czech Academy of Sciences Publication Activity Database

    René, Miloš

    2013-01-01

    Roč. 20, 1/2 (2013), s. 145-147 ISSN 1212-6209 R&D Projects: GA MŠk ME10083 Institutional support: RVO:67985891 Keywords : granite * petrology * geochemistry * Moldanubian Zone Subject RIV: DB - Geology ; Mineralogy

  16. Sea Dredged Gravel versus Crushed Granite as Coarse Aggregate for Self Compacting Concrete in Aggressive Environment

    DEFF Research Database (Denmark)

    Sørensen, Eigil V.; Kristensen, Lasse Frølich

    2007-01-01

    Properties of self compacting concrete (SCC) with two types of coarse aggregate - sea dredged gravel with smooth and rounded particles and crushed granite with rough and angular particles - have been studied. Sea gravel allowed a higher aggregate proportion in the concrete leading to a higher...

  17. Study of isotopic desequilibrium of natural radioactive series in granitic environment: Pluton of El Berrocal (Toledo)

    International Nuclear Information System (INIS)

    Hernandez Benitez, A.

    1994-01-01

    This report summarizes the work funded by European Communities with contract '' The Berrocal project: characterization and validation of natural radionuclide migration processes under real conditions in a fissured granitic environment''. The author takes into account the following aspects in his study: isotope of natural radionuclides, sampling methods, analytic methodology and geological characteristics of the area

  18. Isotopic data revaluation from Cabo province, with base in Cabo granite petrographic studies

    International Nuclear Information System (INIS)

    Legrand, J.M.; Figueiredo Filho, O.A.

    1979-01-01

    The Sto Agostinho's Cape granite (NE-Brazil) is formed by two successive instrusions: the first riolitic or migmatitic, replaced by the alkali granite. This process is indicated by the potassic feldspar phenocrystals porpliroblastic assimilation of the riolites, conglobating the re-cristalized matrix minerals. This two times formation is confirmed by geochronological studies in magmatic province. The diagram of the different rocks with alkaline differentiation is distributed in two isochrons. The first isochron age of 135 m.y +- 0,7 λ=1,42x10 -11 ) with a Ri = 0,7023, the second determine to the Cape granite 104 m.y +- 0,7 (λ=1,42x10 -11 ) with a Ri=0,7058. The first pulsation value of 0,7023, indicate a crust origin to the granite. The more elevated value in the second magmatic dike can be explain by the mixture of more or less 99% of crust magma and 1% of plutonic rocks. (C.D.G.) [pt

  19. SITE-94. Estimated rates of redox-front migration in granitic rocks

    International Nuclear Information System (INIS)

    Arthur, R.C.

    1996-10-01

    Analytical models for the rate of migration of oxidizing groundwaters are derived based on the stationary-state approximation to coupled fluid flow and water-rock interaction, and are constrained by molar concentrations of ferrous silicate, oxide, and sulfide minerals in the granites and associated fractures comprising the host rock beneath Aespoe. Model results indicate that small amounts of ferrous minerals in Aespoe granites and fractures will retard the downward migration of oxidizing conditions that could be generated by infiltration of glacial meltwaters during periods of glacial maxima and retreat. Calculated front velocities are retarded relative to Darcy fluxes observed in conductive fracture zones at Aespoe (0.3 to 3 m/y) by factors ranging from 10 -3 to 10 -4 . Corresponding times for the front to migrate 500 m vary from 5,100 to 4,400,000 years. Retardation efficiency depends on mineralogy and decreases in the order: fractures > altered granites > unaltered granite. The most conductive structures in these rocks are therefore the most efficient in limiting the rate of front migration. Periods of recharge during glaciation are comparable to times required for an oxidizing front to migrate to repository levels. This suggests an oxidizing front could reach repository depths during a single glacial-interglacial event. The persistence of oxidizing conditions could be relatively short lived, however, because reversal of flow conditions driven by the advance and retreat of ice sheets could cause reducing conditions to be restored. 27 refs

  20. Investigation on the Suitability of Fobur Granite in Jos, Plateau State ...

    African Journals Online (AJOL)

    ADOWIE PERE

    was calculated using equation (ISRM, 1981). = ( ). (1). = (2). Porosity Determination of Granite Samples: The samples A, B, C were in seize of cubic, 10mm by. 10mm by 10mm.The samples were then dried in an oven at 110o C. The dry weight of the samples in air were taken and recorded as W1,The sample in air was.

  1. Experimental Investigation of Crack Extension Patterns in Hydraulic Fracturing with Shale, Sandstone and Granite Cores

    Directory of Open Access Journals (Sweden)

    Jianming He

    2016-12-01

    Full Text Available Hydraulic fracturing is an important method of reservoir stimulation in the exploitation of geothermal resources, and conventional and unconventional oil and gas resources. In this article, hydraulic fracturing experiments with shale, sandstone cores (from southern Sichuan Basin, and granite cores (from Inner Mongolia were conducted to investigate the different hydraulic fracture extension patterns in these three reservoir rocks. The different reactions between reservoir lithology and pump pressure can be reflected by the pump pressure monitoring curves of hydraulic fracture experiments. An X-ray computer tomography (CT scanner was employed to obtain the spatial distribution of hydraulic fractures in fractured shale, sandstone, and granite cores. From the microscopic and macroscopic observation of hydraulic fractures, different extension patterns of the hydraulic fracture can be analyzed. In fractured sandstone, symmetrical hydraulic fracture morphology could be formed, while some micro cracks were also induced near the injection hole. Although the macroscopic cracks in fractured granite cores are barely observed by naked eye, the results of X-ray CT scanning obviously show the morphology of hydraulic fractures. It is indicated that the typical bedding planes well developed in shale formation play an important role in the propagation of hydraulic fractures in shale cores. The results also demonstrated that heterogeneity influenced the pathway of the hydraulic fracture in granite cores.

  2. Ilmenit z dvojslídných granitů klenovského plutonu

    Czech Academy of Sciences Publication Activity Database

    René, Miloš

    2013-01-01

    Roč. 46, Prosinec (2013), s. 224-227 ISSN 0514-8057 R&D Projects: GA MŠk ME10083 Institutional support: RVO:67985891 Keywords : ilmenite * two-mica granite * Moldanubian Zone * Bohemian Massif Subject RIV: DB - Geology ; Mineralogy http://www.geology.cz/zpravy/obsah/2012/Zpravy_2012-45.pdf

  3. Geological interpretation of gravity profiles through the Karlovy Vary granite massif (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Blecha, V.; Štemprok, M.; Fischer, Tomáš

    2009-01-01

    Roč. 53, č. 3 (2009), s. 295-314 ISSN 0039-3169 Institutional research plan: CEZ:AV0Z30120515 Keywords : Variscan granites * gravity modeling * Western Bohemia * Saxothuringian zone * Eger Graben Subject RIV: DC - Siesmology, Volcanology, Earth Structure Impact factor: 1.000, year: 2009

  4. Accessory minerals of the Cínovec (Zinnwald) granite cupola, Czech Republic: indicators of petrogenetic evolution

    Science.gov (United States)

    Johan, Z.; Johan, V.

    2005-01-01

    A fully cored drillhole was drilled to 1596 m by the Czech Geological Survey in 1961 1963 in the central part of the Cínovec (Zinnwald) granite cupola. Two types of granite were intersected: zinnwaldite granite (ZG), observed down to a depth of 730 m, and protolithionite granite (PG), occurring to the end of the hole. The core was used to study the distribution and chemistry of: zircon, thorite, xenotime, monazite, bastnäsite, synchysite, REE oxyfluorides and hydroxyfluorides. Zircon occurs throughout the drillcore; it is strongly hydrated and fluorinated with about 18.5 wt.% H2O content in the apical part of the cupola. Its F-content reaches 2.41 wt.%. Within the PG, the F concentration in zircon is low. Zircon is poor in Th and U and its HfO2 contents vary from 1.01 to 5.24 wt.%. Thorite is common in the PG, becoming rare in the ZG. It is strongly hydrated (up to 14 wt.% H2O) and fluorinated (up to 2.04 wt.% F). Extensive solid solution between ThSiO4 and YPO4 was observed. Xenotime is strongly hydrated (up to 16 wt.% H2O), but its F content is low (cupola, and exhibit REE distribution patterns characterized by a weak negative Eu anomaly (synchysite-(Ce)), or a weak positive Eu anomaly (synchysite-(Y)).

  5. Magnetic fabric transposition in folded granite sills in Variscan orogenic wedge

    Science.gov (United States)

    Závada, Prokop; Calassou, Thibaud; Schulmann, Karel; Hrouda, František; Štípská, Pavla; Hasalová, Pavlína; Míková, Jitka; Magna, Tomáš; Mixa, Petr

    2017-01-01

    New approach involving evaluation of anisotropy of magnetic susceptibility (AMS) data in stereoplots and Jelínek's Pj-T space, Vollmer's eigenvalue and microstructural analyses is proposed to discriminate between homogeneous and superposed deformation in granites. This method is used to decipher the internal AMS fabric and microstructural evolution of a folded array of granitic sills. The studied major sill shows a fabric and microstructural zonality marked by submagmatic and high-temperature Type I planar-linear fabric developed at sill margins, and the transpositional Type II subsolidus fabrics that formed at high to medium temperature deformation in the sill core. While Type I fabric is associated with dip slip magnetic lineations, Type II subsolidus fabrics are marked by subhorizontal magnetic lineations striking parallel to the long axis of the sill. The structural reconstruction of the fabrics in the granite and the host rocks as well as new U-Pb zircon ages suggest coeval emplacement of horizontal and vertical sills accounting for significant weakening of the host rock-magma multilayer. The model of folding of such multilayer and extrusion of residual magma parallel to axial planes is discussed with respect to structural record in other syn-contractional granite sill arrays forming sheeted plutons worldwide.

  6. Xenotime-zircon solid solutions in topaz granites of the Saxothuringian Zone

    Czech Academy of Sciences Publication Activity Database

    René, Miloš

    -, - (2010), s. 450 ISSN 0365-8066. [IMA. 21.08.2010-27.08.2010, Budapest] R&D Projects: GA MŠk ME10083 Institutional research plan: CEZ:AV0Z30460519 Keywords : granite * acdessory minerals * Bohemian Massif Subject RIV: DB - Geology ; Mineralogy

  7. Vertical Spindle Grinding of Si and Granite with a New Abrasive Disk

    Directory of Open Access Journals (Sweden)

    Yiqing Yu

    2013-01-01

    Full Text Available An investigation was reported of a new attempt in the fabrication of an ultrafine abrasive tool for vertical spindle grinding. The principle of sol-gel was applied to granulate ultra-fine abrasives in order to reduce their aggregation. The granulated abrasives were then added to resin bonds, thereby forming ultra-fine abrasive grinding disks. Before grinding, the disks were dressed to expected flatness using a brazed diamond pad. The dressed grinding disks were then used to grind silicon wafers and natural granite. Both dressing and grinding were conducted on a high precision vertical spindle grinding machine. After grinding, the morphologies of the workpiece materials were examined. With regard to the different concerns for silicon wafers and granite, surface roughness was measured for the silicon wafers and gloss readings were measured for the granite surfaces. It was found that the brazed diamond abrasives could dress the grinding disks with high efficiency and satisfactory flatness. The new ultra-fine abrasive disks were found to be able to process silicon wafers and granite slabs to acceptable results.

  8. Rootless calc-silicate folds in granite: An implication towards syn to ...

    Indian Academy of Sciences (India)

    36

    Precambrian stratigraphic units and its relation with the study area. The inferences derived. 20 .... Mamtani M A, Greiling R O 2005 Granite emplacement and its relation with regional. 16 deformation in the Aravalli .... Gujarat. Abstract. International seminar on the precambrian crustal evolution of central and. 10 eastern India.

  9. Determination of the sorption coefficients of uranium(VI) in Grimsel and Boettstein granite

    International Nuclear Information System (INIS)

    Wernli, B.; Bajo, C.; Bischoff, K.

    1985-02-01

    A batch method has been used on powdered granites and the sorption coefficients (Rd) of uranium(VI) found are presented. Rock material from the Grimsel and from drill core at Boettstein were used. The sorption coefficient was obtained by six different experimental series at room temperature and normal atmospheric conditions. The powdered rock samples were held in contact with the uranium containing solution (three types of water used, uranium levels from 2 to 2000 ng/ml) for periods between 3 and 17 weeks. The experiments with a uranium concentration of 2 ng/ml were done with double distilled water. Other experiments were carried out using a slightly mineralized water. A third water type was the highly mineralized water from Saeckingen. The increase of the rock/water ratio from 1/20 to 1/2 gave not only higher Rd values but also favoured a considerable leaching of the uranium content of the granites. Correspondingly in further experiments uranium-233 was used as a tracer. The results of these experiments showed a leaching of the uranium of up to 6% of the total granitic uranium content; the added uranium concentration was therefore considerably increased. As a result of the tracer experiments, Rd values between 3 and 30 ml/g and 3 and 15 ml/g respectively for Grimsel and Boettstein granite were found. (Auth.)

  10. Petrology and geochemistry of granitic stocks from Serrita, PE-Brazil

    International Nuclear Information System (INIS)

    Neves, S.P.

    1986-01-01

    The results of studies about petrology and geochemistry of granitic stocks from Serrita, PE-Brazil are discussed. The geologic mapping in the stocks exposure area were done, for its detailed structure. The results of chemical analysis of major and trace elements and rare earth contents are presented. The data of δ 18 O are also discussed and analysed. (M.C.K.) [pt

  11. Optimization of operating schedule of machines in granite industry using evolutionary algorithms

    International Nuclear Information System (INIS)

    Loganthurai, P.; Rajasekaran, V.; Gnanambal, K.

    2014-01-01

    Highlights: • Operating time of machines in granite industries was studied. • Operating time has been optimized using evolutionary algorithms such as PSO, DE. • The maximum demand has been reduced. • Hence the electricity cost of the industry and feeder stress have been reduced. - Abstract: Electrical energy consumption cost plays an important role in the production cost of any industry. The electrical energy consumption cost is calculated as two part tariff, the first part is maximum demand cost and the second part is energy consumption cost or unit cost (kW h). The maximum demand cost can be reduced without affecting the production. This paper focuses on the reduction of maximum demand by proper operating schedule of major equipments. For this analysis, various granite industries are considered. The major equipments in granite industries are cutting machine, polishing machine and compressor. To reduce the maximum demand, the operating time of polishing machine is rescheduled by optimization techniques such as Differential Evolution (DE) and particle swarm optimization (PSO). The maximum demand costs are calculated before and after rescheduling. The results show that if the machines are optimally operated, the cost is reduced. Both DE and PSO algorithms reduce the maximum demand cost at the same rate for all the granite industries. However, the optimum scheduling obtained by DE reduces the feeder power flow than the PSO scheduling

  12. Hercynian late-post-tectonic granitic rocks from the Fornos de Algodres area (Northern Central Portugal)

    Science.gov (United States)

    Azevedo, M. R.; Nolan, J.

    1998-10-01

    The Fornos de Algodres Complex (FAC) comprises several intrusions of late-post-tectonic Hercynian granitic rocks ranging in composition from hornblende granodiorites and quartz monzodiorites, through coarse porphyritic biotite granites and two-mica granites (coarse-, medium- and fine-grained), to muscovite-rich leucogranites. Field and regional constraints show that the emplacement of this large, composite, batholithic complex post-dates the main Variscan regional deformation phases (D 1+D 2+D 3) and associated metamorphic events. Field, petrographic and geochemical data suggest a strong genetic relationship between most of the members of the FAC. However, their Rb-Sr and Sm-Nd isotopic signatures appear to rule out any genetic process involving a single homogeneous source and/or closed-system fractional crystallization of the same parental magma. A model involving hybridization of mantle-derived basaltic liquids with crustal anatectic melts followed by further contamination and fractional crystallization is proposed to explain the isotopic and geochemical variation trends defined by the FAC granitic rocks.

  13. Influence of the properties of granite and sandstone in the desalination process by electrokinetic technique

    DEFF Research Database (Denmark)

    Feijoo, J.; Ottosen, Lisbeth M.; Pozo-Antonio, J.S.

    2015-01-01

    such as sand disaggregation and superficial detachments. These problems can be solved by conservation technologies, which are aimed to decrease the salt concentration in rocks (desalination).The present study aimed to investigate the efficiency of electrokinetic techniques for desalination of two different...... in the granite samples (favored a faster desalination process)....

  14. Source composition and melting temperatures of the main granitic suites from the Moldanubian Batholith

    Czech Academy of Sciences Publication Activity Database

    René, Miloš

    2016-01-01

    Roč. 61, č. 4 (2016), s. 355-370 ISSN 1802-6222 Grant - others:Austrian Science Fund(AT) I1993 Institutional support: RVO:67985891 Keywords : granites * petrology * geochemistry * Moldanubian Zone * Bohemian Massif Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.609, year: 2016

  15. Two-mica granites from the triple-point of Czech Republic, Germany and Austria

    Czech Academy of Sciences Publication Activity Database

    Breiter, Karel; Koller, F.; Scharbert, S.; Siebel, W.; Škoda, R.; Frank, W.

    2007-01-01

    Roč. 147, 3-4 (2007), s. 527-544 ISSN 0016-7800 Institutional research plan: CEZ:AV0Z30130516 Keywords : granites * petrology * accessory minerals Subject RIV: DB - Geology ; Mineralogy http://www.geologie.ac.at/filestore/download/JB1473_527_A.pdf

  16. Geochemical characteristics of Proterozoic granite magmatism from Southern Granulite Terrain, India: Implications for Gondwana

    Science.gov (United States)

    Yellappa, T.; Rao, J. Mallikharjuna

    2018-03-01

    Granitoid intrusions occur widely in the Southern Granulite Terrain (SGT) of India, particularly within the Cauvery Suture Zone (CSZ), which is considered as the trace of the Neoproterozoic Mozambique ocean closure. Here we present the petrological and geochemical features of 19 granite plutons across the three major tectonic blocks of the terrain. Our data show a wide variation in the compositions of these intrusions from alkali feldspathic syenite to granite. The whole rock geochemistry of these intrusions displays higher concentrations of SiO2, FeO*, K2O, Ba, Zr, Th, LREE and low MgO, Na2O, Ti, P, Nb, Y and HREE's. The granitoids are metaluminous to slightly peraluminous in nature revealing both I-type and A-type origin. In tectonic discrimination plots, the plutons dominantly show volcanic arc and syn-collisional as well as post-collisional affinity. Based on the available age data together with geochemical constrains, we demonstrate that the granitic magmatism in the centre and south of the terrain is mostly associated with the Neoproterozoic subduction-collision-accretion-orogeny, followed by extensional mechanism of Gondwana tectonics events. Similar widespread granitic activity has also been documented in the Arabian Nubian shield, Madagascar, Sri Lanka and Antarctica, providing similarities for the reconstruction of the crustal fragments of Gondwana supercontinent followed by Pan-African orogeny.

  17. Fabric transpositions in granite plutons - an insight from non-scaled analogue modelling

    Czech Academy of Sciences Publication Activity Database

    Kratinová, Zuzana; Machek, Matěj; Kusbach, V.

    2010-01-01

    Roč. 75, č. 1 (2010), s. 267-277 ISSN 0016-7622 R&D Projects: GA AV ČR KJB300120702 Institutional research plan: CEZ:AV0Z30120515 Keywords : analogue modelling * magmatic fabrics * granite intrusions * rheology * AMS Subject RIV: DB - Geology ; Mineralogy Impact factor: 0.396, year: 2010

  18. Validation of modeling team solution and matrix porosity of granitic rocks

    Czech Academy of Sciences Publication Activity Database

    Vaněček, M.; Hanuš, R.; Doležalová, L.; Michálková, J.; Rousová, P.; Sosna, K.; Křížová, H.; Záruba, J.; Navrátil, Tomáš; Nakládal, P.; Brož, M.; Rohovec, Jan; Polák, M.; Milický, M.

    2008-01-01

    Roč. 34, 4/6 (2008), s. 1343396-1343396 ISSN 0161-6951. [International Geological Congress /33./. 06.08.2008-14.08.2008, Oslo] R&D Projects: GA MPO 1H-PK/31 Institutional research plan: CEZ:AV0Z30130516 Keywords : radioactive waste * granite * hydrogeology * modeling * porosity Subject RIV: DD - Geochemistry

  19. Protocol proposal for radon concentration mensuration from granitic rocks in marble factory

    International Nuclear Information System (INIS)

    Del Claro, Flavia

    2016-01-01

    Naturally occurring radionuclides such as radon ( 222 Rn), its decay products and other elements from the radioactive series of uranium ( 238 U and 235 U) and thorium ( 232 Th) are an important source of human exposure to natural radioactivity. The worldwide evaluation of health radiobiological effects and risks from population exposure to natural radionuclides is a growing concern. Radionuclides such as radon ( 222 Rn), the thoron ( 220 Rn), radio ( 2 '2'6Ra), thorium ( 23 '2Th) and potassium ( 40 K) may occur in materials commonly used in construction of dwellings and buildings. Thus, the radioactivity from marbles and granites is of importance, so that under certain conditions these materials radioactivity levels can be hazardous requiring the implementation of mitigation measurements. This research presents a technical protocol marble factories for the control human exposure to natural radioactivity exhaled from granitic rocks. The protocol was based on measurements of the 222 Rn and 220 Rn concentration in Brazilian granite rocks commonly nationally and exported. The 222 Rn and 220 Rn measurements were done using the AlphaGUARD (Saphymo GmbH) and RAD7 (Durridge Company) apparatus, respectively. The samples of granite were sealed in glass jars for 40 days in to achieve secular equilibrium between 226 Ra and 222 Rn radionuclides. The measurements were performed on Applied Nuclear Physics Laboratory at the Federal Technological University of Parana. Also, solid-state nuclear track detectors CR-39 were installed in a marble factory environments located in Curitiba - Parana for the evaluation of 222 Rn concentrations in workplaces. The CR-39 detectors were exposed for about 90 days and submitted to etching process. The alpha particle tracks were observed using an optical microscope. Some granite samples analyzed presented 222 Rn concentrations of attention, since the average values ranged from 3 ± 1 Bq/m 3 to 2087 ± 19 Bq/m 3 . The results obtained

  20. Preserved magnetic fabrics vs. annealed microstructures in the syntectonic recrystallised George granite, South Africa

    Science.gov (United States)

    Ferré, E. C.; Améglio, L.

    2000-08-01

    The Saldanian basement of the Cape Fold Belt of South Africa outcrops in the Kaaimans inlier with granite plutons intruded in low-grade pelitic and quartzitic metasediments around 535 Ma. New field data support a ubiquitous Saldanian top-to-the-north thrust kinematics coeval with granite emplacement with no substantial Cape tectonic overprint. The granites and their contact aureoles display both synkinematic and post-kinematic fabrics. This and the high strain zone commonly observed all along the contact between the Kaaimans inlier and the Cape Fold Belt, suggest a structural decoupling between the basement and its cover. Microstructures in the Kaaimans inlier and in the George pluton establish a post-kinematic, pervasive and thermal overprint of Saldanian age. Granites and country rocks record a medium-temperature/high-strain deformation phase followed by a strong low-temperature/static recrystallisation. Two sets of andalusite porphyroblasts occur systematically in the contact aureoles of the studied plutons and cannot be explained by successive magmatic pulses. The granites, studied by the Anisotropy of Magnetic Susceptibility (AMS) technique, are paramagnetic (20law) and on intrinsic mineral susceptibilities. The magnetic foliations and lineations are homogeneous throughout the George pluton and are consistent with field structures. The AMS results mainly from the magneto-crystalline anisotropy of biotite and from its lattice preferred orientation (LPO) in the rock. The magnetic fabric reveals the biotite subfabrics that had been acquired before static recrystallisation and which was not modified by the subsequent thermal metamorphic event. The magnetic fabric therefore preserves the emplacement-related deformation fabric.

  1. Long-term solute diffusion in a granite block immersed in sea water

    International Nuclear Information System (INIS)

    Jefferies, N.L.

    1988-01-01

    Solute diffusion profiles for Cl - , Br - , F - and SO 4 -- have been measured in a granite block which was immersed in the sea at Falmouth, Cornwall, for 30 years. Leachable concentrations of Cl - and Br - were found to be higher in the block than in quarry samples of granite, which demonstrates that solutes from the sea water have diffused into the block. The Cl - and Br - profiles within the block were flat, implying that equilibrium has been reached between the seawater and granite porewater. The apparent diffusion coefficient and the solute accessible porosity have been estimated from these profiles, and these were used to calculate the intrinsic diffusion coefficient which was then compared with previously obtained laboratory data. Concentration profiles for F - and S0 4 -- indicate that these elements have high concentrations at the margins of the block (to depths of up to 15 cm) and are in the process of diffusing outwards into the surrounding seawater. The initially high porewater concentrations of F - and SO 4 -- in the block are believed to result from weathering of the granite prior to its immersion in the sea, due to the breakdown of primary minerals such as pyrite and the micas. F - and SO 4 -- sorptivity has been estimated from an analysis of the porewater concentration profiles. This preliminary experiment has demonstrated the potential for the measurement of solute migration in granite, as a result of the rock having been immersed in seawater. This work is part of the CEC project MIRAGE (radionuclide migration in the geosphere)- Second phase (1985-89) Research area 'Natural analogues'

  2. Mineral chemistry of polymetallic mineralization associated with altered granite, Hangaliya area, South Eastern Desert, Egypt

    Directory of Open Access Journals (Sweden)

    Mohamed F. Raslan

    2010-12-01

    Full Text Available The Hangaliya gold deposit, located in the South Eastern Desert of Egypt, comprises a series of milky quartzveins along NW-trending Hangaliya shear zone, cutting through granitic rocks of Gabal Nugrus monzogranite. Thisshear zone, along with a system of discrete shear and fault zones, formed in the late deformation history of the area.The quartz vein emplacement took place under a brittle-ductile shear regime. Auriferous quartz veins are slightlysheared and boudinaged within the shear zone, especially in the hematized granite. Hydrothermal alteration ispervasive in the granitic wall rocks including sericitization, chloritization, fluoritization, sulphidization and minorcarbonatization. The altered zones and associating quartz veins contain sulphides, gold, silver, cobalt, bismuth, anduraninite minerals.The Hangaliya gold veins include gold, silver, cobaltite, native bismuth, chalcopyrite, pyrite, galena, ferrocolumbite,fergusonite and uraninite. The Au-ore occurs in the quartz veins and adjacent wall rocks as disseminationin chalcopyrite and pyrite. Presence of refractory native silver, bismuth and cobalt in chalcopyrite is inferredfrom microprobe analyses. Wall rock sulphidization also likely contributed to destabilising the gold-silver, cobalt,bismuth assemblages and precipitation of the minerals in the hydrothermal alteration zone adjacent to the quartzveins. Gold occurs in two main modes: “invisible gold” in sulphides and native gold. Most of the “invisible gold”occurs in chalcopyrite and bismuth. The altered granites in the Hangaliya shear zone are enriched in Au, Ag, Bi, Co,and Ni with chalcopyrite, which suggests derivation of these metals from serpentinites due to interaction with thefelsic Nugrus granite.

  3. Site selection methods for nuclear waste storage in sub-schistic granites

    International Nuclear Information System (INIS)

    Alsac, C.; Chantraine, J.; Chevremont, P.

    1984-02-01

    Intrusive granites in schists, where most of the roof is at a depth of several hundred metres can be regarded as favourable sites for storing radioactive waste since the schistic cover has extremely low permeability. This configuration exists in various parts of France. In this paper the authors describe methods which can be applied to the study of such structures, taking a region in the Armorican Massif as a reference example. The geological evidence here showed an extensive zone with a slight gravimetric anomaly around a few granite outcrops dispersed in the schists. This structure gave reason to believe that a shallow granite mass would be found under the schistic cover, and geological and gravimetric surface studies did indeed prove that this supposition was correct. Apart from the slight gravimetric anomaly, the extent of which has been confirmed and the outlines determined, the transformations (contact metamorphism and hydrothermalism) of the enclosing schists are particularly indicative of the presence of granite. The gravimetric model shows that the thickness of the granite is at least 2.3 km and provides an initial representation of the shape and depth of the roof. These results, together with those of the structural analysis, can be used to demarcate a favourable region for investigations at depth which will make it possible: to monitor the geological structures; to define the geotechnical characteristics of the formations; to analyse and model the hydrogeological behaviour, at present known only from surface studies which do not appear to indicate any circulation of water upwards towards the surface

  4. Patherns in the rare earth elements of the Serra do Carambei granite (Parana) and the others associated ignous rocks

    International Nuclear Information System (INIS)

    Pinto-Coelho, C.V.; Marini, O.J.

    1986-01-01

    The rare earth elements (REE) distribution patters in igneous rocks of the Serra do Carambei Granite area (Parana) were a very important tool to elucidate the genetic processes and the cogenetic relationships between these rocks. The porphyroid facies of the Cunhaporanga Granitoid Complex has a REE distribution pattern characterized by decreasing concentrations in direction to the heavy rare earth elements (HREE) and the smooth Eu negative anomalie, compatible with amphibole fractionation during the magma ascent and the incipient plagioclase fractionation. The REE pattern of the Serra do Carambei Granite is characterized by the strong Eu negative anomalie, by the light rare earth element (LREE) depletion and by the HREE increase. This shape of the REE patterns is frequently observed in Sn-W granites, according to French authors. However in the igneous rocks of the Serra do Carambei Granite area this is not true. ''Rhyolite'' dytes intrusives in the Serra do Carambei Granite exhibit REE pattern similar to the wall rock, indicating then the same genetic processes. The Castro Group rhyolites have REE patterns with decreasing concentrations in direction to the HREE and smooth Eu negative anomalie. The REE distribution patterns is against the consanguinity between the ''rhyolites'' intruded in the Serra do Carambei Granite and the rhyolites of the Castro Group and also between these rhyolites and the above mentioned Granite. (author) [pt

  5. Genesis of Uranium in the younger granites of gabal abu hawis area, central eastern desert of Egypt

    International Nuclear Information System (INIS)

    Ahmed, F.Y.; Moharem, A.F.

    2003-01-01

    The younger granites cropping out in gabal abu hawis area are considered as uraniferous (fertile) granites (the fertile is mainly is mainly attributed to presence of radioactive zircon). Abu hawis granitic pluton is dissected by joints faults of different trends forming two mineralized shear zones in the northern peripheries and southern border. The younger granites hosting uranium mineralizations along the two mineralized shear zones. The uranium minerals include uranophane and carnotite. The altered granites have much lower Th/U ratios (0.03-0.10) than those of the fresh granites (1.69-2.05), indicating strong mobilization of uranium in this pluton by super-heated solutions that resulted from supergence meteoric water as well as U-addition by hypogene fluids. These solutions could pass through the structural network of fractures, joints and fault planes and have leached some of labile uranium from the surrounding rocks and/or the younger granites themselves. Then, changing in the physicochemical conditions of these solutions caused uranium precipitation as uranium minerals filling the cracks in the rock and/or adsorbed on the surface of clay minerals and iron oxides in the two shear zones

  6. Geochemistry of the uranium mineralized Achala granitic complex, Argentina: Comparison with Hercynian peraluminous leucogranites of western Europe

    International Nuclear Information System (INIS)

    Cuney, M.; Leroy, J.; Valdiviezo, P.A.; Daziano, C.; Gamba, M.; Zarco, A.J.; Morello, O.; Ninci, C.; Molina, P.

    1989-01-01

    The Achala granitic complex belongs to the Sierras Pampeanas Hercynian belt, located west of the city of Cordoba, Argentina. This complex is very large (about 100 km N-S and 40 km E-W) and is composed of biotite, biotite with muscovite and muscovite with tourmaline granites intruded in amphibolite grade metamorphic rocks, along a main N 20 deg. E structural direction. Numerous uranium mineralizations are located within the granitic massif and tungsten mineralizations are present both in the enclosing metamorphic rocks and in the granite. The geochemistry of the granite has been studied in four test areas (Southern, Copina, Median and Don Vincente). Two test areas (Median and Don Vicente) present clear evidence of hydrothermal alteration: albitization and dequartzification similar to the French 'episyenites', silicification and argillic alteration. Potassic alteration is rare and weakly developed. The two test areas with hydrothermal alteration present a high uranium geochemical background (5-30 ppm). High thorium contents (up to 65 ppm) are essentially observed in the less differentiated granites of the Copina and Median areas. Thorium/uranium ratios are highly variable (1-10). Uranium minerals are related to different environments - (1) apatite-biotite enclave mineralized with uraninite and uranothorite, (2) gneiss from the contact metamorphism rim, (3) granite with incipient dequartzification, (4) granite associated with albitic episyenites and (5) silicified granite - but are all located in the two test areas presenting clear evidence of hydrothermal alteration. The three petrogenetic events are clearly related to very different mechanisms, separated from each other by several tens of millions of years in the west European Hercynian chain. In the same period the same succession of events leading to uranium deposits is observed in Argentina. 34 refs, 10 figs, 1 tab

  7. Coastal placer minerals

    Digital Repository Service at National Institute of Oceanography (India)

    Iyer, S.D.; Gujar, A.R.

    could then indicate whether the minerals can be exploited economically for use. If so, then the requisite permissions and licenses need to be obtained to mine the sands from the government. The sands can either be used within the country..., Australia, USA, Canada, South Africa, Sri Lanka, Brazil, Norway and Malaysia. India is blessed with a long coastline of more than 7500 km, including islands. The erosion of rocks results in coastal placers such as rutile, ilmenite, zircon, monazite...

  8. Coastal research: Observational challenge

    Digital Repository Service at National Institute of Oceanography (India)

    Nayak, M.R.

    . Thus, two important aspects are near real-time data telemetry and data assimilation modeling. It is evident that marine technologies face challenges not only in the natural scales of coastal environmental variability, but also in par ticular... fluctuations in phytoplankton biomass, phy toplankton blooms associated with incipient seasonal stratification, and frontal- and eddy-trapped inertial waves. Measurements of nitrate, partial pressure of carbon dioxide (pC0 2 ), and dissolved oxygen (DO) have...

  9. Coastal risk forecast system

    Science.gov (United States)

    Sabino, André; Poseiro, Pedro; Rodrigues, Armanda; Reis, Maria Teresa; Fortes, Conceição J.; Reis, Rui; Araújo, João

    2018-03-01

    The run-up and overtopping by sea waves are two of the main processes that threaten coastal structures, leading to flooding, destruction of both property and the environment, and harm to people. To build early warning systems, the consequences and associated risks in the affected areas must be evaluated. It is also important to understand how these two types of spatial information integrate with sensor data sources and the risk assessment methodology. This paper describes the relationship between consequences and risk maps, their role in risk management and how the HIDRALERTA system integrates both aspects in its risk methodology. It describes a case study for Praia da Vitória Port, Terceira Island, Azores, Portugal, showing that the main innovations in this system are twofold: it represents the overtopping flow and consequent flooding, which are critical for coastal and port areas protected by maritime structures, and it works also as a risk assessment tool, extremely important for long-term planning and decision-making. Moreover, the implementation of the system considers possible known variability issues, enabling changes in its behaviour as needs arise. This system has the potential to become a useful tool for the management of coastal and port areas, due to its capacity to effectively issue warnings and assess risks.

  10. Coastal remote sensing – towards integrated coastal research and management

    CSIR Research Space (South Africa)

    Lück-Vogel, Melanie

    2012-10-01

    Full Text Available million (UNESCO, 2009). The destructive forces of storms mainly results from the impact of: ? Waves, leading to shoreline erosion ? Wind ? Flooding. Coastal areas which are low-lying and sandy are particularly vulnerable, as can be found along most... such as shoreline erosion or flooding. Coastal remote sensing, as we define it, is bridging the gap between classic terrestrial and marine remote sensing. However, to date, coastal remote sensing competency and applications are very scarce and undeveloped...

  11. 75 FR 9158 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; Coastal Sharks Fishery

    Science.gov (United States)

    2010-03-01

    ... Coastal Fisheries Cooperative Management Act Provisions; Coastal Sharks Fishery AGENCY: National Marine... Commission's Interstate Fishery Management Plan (ISFMP) for Coastal Sharks. Subsequently, the Commission... New Jersey failed to carry out its responsibilities under the Coastal Sharks ISFMP, and if the...

  12. Assessment of natural radioactivity in commercial marble and granite of Espirito Santo state

    International Nuclear Information System (INIS)

    Aquino, Reginaldo Ribeiro de

    2015-01-01

    In this work, the concentrations of natural radionuclides 226 Ra, 232 Th and 40 K in granite and marble samples were determined, considering the main extraction mining of Espirito Santo state, southeastern Brazil. For all study sites, three samples were sealed in 100 ml high density polyethylene bottles. Each sample rested for 4 weeks to reach the secular equilibrium of 238 U and 232 Th series before measured by high resolution gamma spectrometry, and the acquired spectra were analyzed with the software WinnerGamma. The self-absorption correction was considered for all samples, using an expression and method specially developed for this purpose. The concentration of 226 Ra was determined by the weighted arithmetic mean of the concentrations of 214 Pb and 214 Bi, the concentration of 232 Th by the weighted arithmetic mean of the concentrations of 228 Ac, 212 Pb and 212 Bi and the concentration of 40 K by its single 1460 keV transition. The radium equivalent and gamma index were calculated from the activity concentrations of 226 Ra, 232 Th, and 40 K. The emanated radon was measured using an exhalation chamber and the passive detector technique, with a solid state nuclear tracks detectors (SSNTD) being exposed in NRPB/SSI-H dosimeters. During exposure, a commercial detector CR-39® and a national plastic called Durolon® were used, the last was characterized for this purpose using a technique called double exposure and sensitivity intrinsic factor. The characterized plastic was efficient for the application and the calibration factor corresponded to 1.60 ± 0.10 tracks.cm².(kBq.m -3 day) -1 in relation to the CR-39 factor, equivalent to 2.8 ± 0.2 tracks.cm².(kBq.m -3 .day) -1 . The detector showed a higher efficiency at a higher dose. The activities determined by passive detection varyed from 100 ± 10 Bq.m -3 up to 2400 ± 300 Bq.m -3 , highlighting the biggest exhalation rates for granite Ibere Mombasa. Considering the marbles, activity values varyed from 80

  13. Coastal ecosystems, productivity and ecosystem protection: Coastal ecosystem management

    Energy Technology Data Exchange (ETDEWEB)

    Ngoile, M.A.K.; Horrill, C.J. (Inst. of Marine Sciences, Zanzibar (Tanzania, United Republic of))

    1993-01-01

    The coastal zone is a complex ecosystem under the influence of physical, chemical and biological processes. Under natural conditions these processes interact and maintain an equilibrium in the coastal ecosystem. Man makes a variety of important uses of coastal resources, ranging from harvesting of living resources, extraction of nonliving resources, and recreation, to the disposal of wastes. Man's extensive use of the oceans introduces factors which bring about an imbalance in the natural processes, and may result in harmful and hazardous effects to life hindering further use. Man's pressure on the resources of the coastal zone is already manifest and will increase manifold. This calls for an immediate solution to the protection and sustainable use of coastal resources. The current sectorized approach to the management of human activities will not solve the problem because the different resources of the coastal zone interact in such a manner that disturbances in one cause imbalance in the others. This is further complicated by the sectorized approach to research and limited communication between policy makers, managers, and scientists. This paper discusses strategies for managing coastal-resources use through an integrated approach. The coastal zone is presented as a unified ecosystem in equilibrium and shows that man's extensive use of the coastal resources destabilizes this equilibrium. Examples from the East Africa Region are presented. 15 refs, 2 figs, 3 tabs

  14. Coastal ecosystems, productivity and ecosystem protection: Coastal ecosystem management

    International Nuclear Information System (INIS)

    Ngoile, M.A.K.; Horrill, C.J.

    1993-01-01

    The coastal zone is a complex ecosystem under the influence of physical, chemical and biological processes. Under natural conditions these processes interact and maintain an equilibrium in the coastal ecosystem. Man makes a variety of important uses of coastal resources, ranging from harvesting of living resources, extraction of nonliving resources, and recreation, to the disposal of wastes. Man's extensive use of the oceans introduces factors which bring about an imbalance in the natural processes, and may result in harmful and hazardous effects to life hindering further use. Man's pressure on the resources of the coastal zone is already manifest and will increase manifold. This calls for an immediate solution to the protection and sustainable use of coastal resources. The current sectorized approach to the management of human activities will not solve the problem because the different resources of the coastal zone interact in such a manner that disturbances in one cause imbalance in the others. This is further complicated by the sectorized approach to research and limited communication between policy makers, managers, and scientists. This paper discusses strategies for managing coastal-resources use through an integrated approach. The coastal zone is presented as a unified ecosystem in equilibrium and shows that man's extensive use of the coastal resources destabilizes this equilibrium. Examples from the East Africa Region are presented. 15 refs, 2 figs, 3 tabs

  15. Coastal Modeling System Advanced Topics

    Science.gov (United States)

    2012-06-18

    22 June 2012 - Day 5  Debugging and Problem solving  Model Calibration  Post-processing Coastal and Hydraulics Laboratory Focus of...Efficiently: • The setup process is fast and without wasted time or effort 3 Coastal and Hydraulics Laboratory 4 Coastal Modeling System (CMS) What...is the CMS? Integrated wave, current, and morphology change model in the Surface- water Modeling System (SMS). Why CMS? Operational at 10

  16. Black Sea coastal forecasting system

    Directory of Open Access Journals (Sweden)

    A. I. Kubryakov

    2012-03-01

    Full Text Available The Black Sea coastal nowcasting and forecasting system was built within the framework of EU FP6 ECOOP (European COastalshelf sea OPerational observing and forecasting system project for five regions: the south-western basin along the coasts of Bulgaria and Turkey, the north-western shelf along the Romanian and Ukrainian coasts, coastal zone around of the Crimea peninsula, the north-eastern Russian coastal zone and the coastal zone of Georgia. The system operates in the real-time mode during the ECOOP project and afterwards. The forecasts include temperature, salinity and current velocity fields. Ecosystem model operates in the off-line mode near the Crimea coast.

  17. Recent progress of the NEA Stripa project on in situ experiments in granite associated with the disposal of radioactive waste

    International Nuclear Information System (INIS)

    Carlyle, S.G.; Carlsson, H.S.

    1987-01-01

    The NEA Stripa project has devoted considerable effort to the measurement and assessment of the hydrogeology, hydrogeochemistry and migration phenomena of the stripa granite and to the simulation of conditions likely to be found within an engineered repository in granitic rock. These include refining existing, and developing new, geophysical and hydraulic techniques for the mapping and characterization of fractures in crystalline rocks; conducting field experiments to assess the migration of tracers in single-and multiple-fracture systems; and studying the behaviour of bentonite clay as the back-filling and sealing material in a granitic environment. This paper summarizes the most important findings and outlines the main aims of possible future research under any phase 3 of the project. The latter may include making mathematical predictions of the hydrogeological behavior of the Stripa granite and their subsequent validation by field measurements

  18. Lower Snake River Little Goose and Lower Granite Locks and Dams: Adult Fishway Systems Emergency Auxiliary Water Supply

    National Research Council Canada - National Science Library

    Wielick, Rolf

    2000-01-01

    ... to address the Biological Opinion requirement. This Emergency Auxiliary Water Supply, Phase II - Technical Report continues to evaluate the Phase I report alternatives for the Little Goose and Lower Granite Lock and Dams at a greater...

  19. Release, Migration, Sorption, and (RePrecipitation of U during Peraluminous Granite Alteration under Oxidizing Conditions in Central Portugal

    Directory of Open Access Journals (Sweden)

    Marina M. S. Cabral Pinto

    2018-03-01

    Full Text Available In this work, in order to study the release, migration, sorption, and (reprecipitation of uranium (U during alteration under oxidizing conditions, we carried out a systematic study using scanning electron microscopy, X-ray maps, and electron microprobe analyses on uranium minerals—such as uraninite, coffinite, saleeite, meta-saleeite, and thorite—and U-bearing minerals—such as xenotime, monazite, apatite, and zircon—from unaltered and altered Variscan peraluminous granites and related hydrothermal brecciated uranium–quartz veins. The paragenetic sequence of the granite and the mineralized quartz veins from Vale the Abrutiga is presented. Uraninite is magmatic in origin and occurs mainly in unaltered granite; it is rare in altered granite, and was not found in the mineralized quartz veins. Uraninite from the altered granite was fractured and hydrated; it had radioactive damage halos filled with late pyrite, U–S-bearing phases, and Fe oxyhydroxides; its analytical totals were also lower than in the uraninite from the unaltered granite. The alteration zones and crystal rims were poorer in U (86.7 wt.% UO2 than in the cores and unaltered zones (90.2 wt.% UO2, and some uraninite crystals were replaced by coffinite, which resulted from uraninite alteration. The U contents in the coffinite crystals ranged between 65.0 wt.% UO2 in the rims to 84.0 wt.% UO2 in the cores of the crystals. Thorite was found in all of the granite samples, and its composition was variable from 0.5 wt.% UO2 to 10.4 wt. % UO2. Some thorite seemed to be primary, whereas the other thorite was related to the granite alteration, replaced apatite and monazite, was associated with xenotime, and filled the fractures of several minerals. In the altered granite, thorite had low UO2 contents (0.46 wt. % in the fractured crystal zones. Monazite from the altered granite had a pervasive porosity; some crystals were formed by the alteration of apatite, and were frequently

  20. Magmatic-hydrothermal evolution of the Kymi topaz granite stock, SE Finland: Mineral chemistry evidence for episodic fluid exsolution

    Science.gov (United States)

    Berni, Gabriel V.; Wagner, Thomas; Fusswinkel, Tobias; Wenzel, Thomas

    2017-11-01

    The Kymi stock is a highly evolved topaz-bearing granite stock that has intruded into rapakivi granites in the central part of the Wiborg batholith (southwest Finland). The stock shows a well-defined zonation and intrusion sequence consisting of early porphyritic granites, subsequent equigranular granite and a late marginal stockscheider pegmatite. Miarolitic cavities occur within all rock types of the stock, but they are more abundant near the contact between the porphyritic and equigranular granites. Related hydrothermal greisen alteration, barren and Pb-Zn mineralized fluorite-bearing quartz veins crosscut the host rapakivi granites close to the Kymi stock. The major and trace element chemistry of biotite, K-feldspar, plagioclase and fluorite tracks the magmatic to hydrothermal evolution of the system. The biotite composition ranges from Al-rich annite to Li-rich siderophyllite, and the biotite chemistry shows an increase in Si, Li, AlVI, F, Mn, Rb, Cs, Zn, Be, Ga, Tl, Ta, and F, and a decrease in Fe, AlIV, Mg, Ti, Ba, Sr, Nb, and Cl along the evolution of the system. The Nb/Ta ratios in biotites suggest that magmatic fractionation is responsible for the progressive Ta enrichment in early porphyritic granites. The subsequent decrease in Nb at rather constant Ta in the more evolved equigranular granite and stockscheider pegmatite cannot be explained by magmatic fractionation, but requires selective partitioning of Nb into an aqueous fluid phase. The halogen composition of the biotites changes drastically from the early porphyritic granites to the later more evolved equigranular granite and stockscheider pegmatite. The Cl/F data of biotite from the miarolitic cavities plots at the transition between the porphyritic and equigranular granites, and is interpreted in terms of major fluid exsolution occurring at this stage. The minor and trace element data of K-feldspar and plagioclase show similar compositional trends as the biotites. The REEY patterns of fluorites

  1. Petrogenesis of the Baishan granite stock, Eastern Tianshan, NW China: Geodynamic setting and implications for potential mineralization

    Science.gov (United States)

    Cao, MingJian; Qin, KeZhang; Li, GuangMing; Evans, Noreen J.; McInnes, Brent I. A.; Lu, WeiWei; Deng, Gang

    2017-11-01

    Located in a region rich in Cu-Ni and Mo mineralization, the Baishan granitic stock is barren for reasons that remain enigmatic. Whole rock elemental and Sr-Nd isotope analysis, major element analysis of a number of minerals, and zircon trace element, U-Pb and Hf isotope analysis were undertaken in order to reveal the petrogenesis of the granites. All granites show typical I-type characteristics including metaluminous to slightly peraluminous, calc-alkaline signatures with a strong depletion of Nb, Ta, Ti and P, enrichment of light rare earth elements and large ion lithophile elements (e.g., Cs, Rb, Th, U, K). In addition, a strong depletion in Ti and P, highly fractionated light rare earth element patterns and less fractionated heavy rare earth element patterns, and negative correlations between SiO2 and TiO2, Al2O3, MgO, FeOT, P2O5, Zr and Hf suggest significant fractional crystallization of amphibole, apatite, zircon and Ti-bearing minerals. Whole rock Sr-Nd and zircon Hf isotopic compositions show wide variations with (87Sr/86Sr)i values of 0.70358 to 0.70505, εNd (t) of 3.8 to 7.2, and εHf (t) of 2.4 to 12.2 indicating derivation from partial melting of juvenile lower crust with obvious addition of ancient crust. Zircon U-Pb ages indicate a formation age of 292 Ma, significantly older than the ore-forming granite porphyry and slightly older than the regional mafic-ultramafic, A-type and diabase magmatism of Eastern Tianshan. The granite stocks were likely derived during heating of ascending asthenospheric mantle above a mantle plume in the Early Permian. Mineral chemistry, saturation thermometry, mineral species and whole rock Fe2O3/FeO ratios indicate a crystallization temperature of > 980 to 665 °C, pressure of 1.6 kbar and oxygen fugacity of ≤ NNO for the granite stock. Comparing the geochemistry, magma source and crystallization environment for the Early Permian barren granite and Late Triassic ore-related granite porphyry, the low ratios of Sr/Y and

  2. Study of the mineralogical transformations of granite by underground nuclear explosions

    International Nuclear Information System (INIS)

    Faure, Jean

    1970-01-01

    The object of the following communication is to prove new data about the petrographic effects of the underground nuclear explosions. It is founded on the results of trench tests in granite rock. The samples are collected by drilling and the temperature of the rock was measured in the hole. Four types of melted rocks can be sorted, grey-green glass and pumices, beige to red-brown pumices, dark lavas, dark veinlets and crushed granite. The distribution of these rocks is studied. Optical microscopy, X-rays and chemical analysis, study by electron probe, are made. The results complete previously published data. They are interesting as far as the use of nuclear explosions for industrial applications is concerned. (author)

  3. The origin of groundwater salinity in granitic rocks: identification and characterisation of chloride sources

    International Nuclear Information System (INIS)

    Savoye, Sebastien

    1998-01-01

    This research thesis aims at clearly identifying the possible origins of chlorine in solution in underground waters in a granitic environment, and is thus a first step in the prediction of concentration of dissolved compounds in waters in crystalline environment, with respect to the geological context. In a first part, the author proposes a synthetic and critical overview of knowledge and previous studies: definition of the term 'salinity', presentation of geochemical tracers, presentation of available data on potential chlorine sources in granitic rocks. The author then describes the experimental protocols and studied sites, reports results of the characterisation of different chlorine tanks performed on samples from each studied site. Based on mass assessment calculations and on the use of tracers, the author finally discusses the contribution of each of the chlorine tanks to the salinity of underground waters [fr

  4. The Pedregal granite (Portugal: petrographic and geochemical characterization of a peculiar granitoid

    Directory of Open Access Journals (Sweden)

    Ferreira, J. A.

    2014-12-01

    Full Text Available The Pedregal granite outcrops in the Central Iberian Zone, northern Portugal, in the eastern border of a synorogenic variscan granite-migmatite complex sub-concordant with the regional metamorphic structures. It is a granitoid (ca. 3 km2 with an elongated NW-SE shape intruded in staurolite-micaschist and banded gneiss-migmatite rocks, with local igneous breccias in the contact. The country rocks belong to a metapelitic and metasammitic sequence of Edicarian-Cambrian age, known as the “Complexo Xisto-Grauváquico” (CXG which shows a main regional foliation with a NW-SE to NNW-SSE direction. The Pedregal granite is peraluminous (its A/CNK parameter ranges from 1.18 to 1.62, with a magnesian and alkali to alkali-calcic signature. The peculiar features of the granite are high contents of Zr (389 to 435 ppm and a LREE flat pattern, which are uncommon characteristics for granitic rocks, as well as the corroded shape of the biotite, and the large amount of secondary muscovite. These peculiar features distinguish it from the adjacent synorogenic granites. The field, petrographical and chemical features of the Pedregal granite are in accordance with a second phase of partial melting of a residuum, depleted by melt segregation during a first melting episode with the involvement of peritectic garnet and abundant residual biotite with LREE- and Zr-bearing accessory minerals. Besides, the intrusive character of the granite, and the presence of metasedimentary xenoliths point out to a secondary diatexite.El granito de Pedregal aflora en la Zona Centro-Ibérica, en el norte de Portugal, en el borde oriental de un complejo granito-migmatítico sinorogénico varisco, subconcordante con las estructuras metamórficas regionales. Es un granitoide (ca. 3 km2 de forma elongada NW-SE, que intruye en micaesquistos estaurolíticos y en rocas gneissico- migmatíticas bandeadas, con brechas ígneas locales en el contacto. Las rocas encajantes pertenecen a una

  5. Geological environment and mineralizations associated to granite from Serra Dourada (meridional edge) - Goias

    International Nuclear Information System (INIS)

    Macambira, M.J.B.

    1983-01-01

    The Serra Dourada granite is related to one of the various large tin-bearing domic structures that occur in central-eastern Goias, where rocks of Uruacu and Brasilia folded belts and of Goias median massif crop out. The present study was undertaken in the southern part of Serra Dourada as an attempt to contribute to the petrologic, metallogenetic and stratigraphic aspects of the granitic rocks present in that region. The methodological approach consisted of the preparation of a 1:45.000 geological map and included the obtention of petrographic, ore microscopic and geochronological data, as well as the determination of major element concentrations in rocks and some minerals. Trace elements were only determined for rocks. (author)

  6. An oxygen isotope study on hydrothermal sources of granite-type uranium deposits in South China

    International Nuclear Information System (INIS)

    Yongfei, Z.

    1987-01-01

    The usefulness of oxygen isotope measurements in solving problems of hydrothermal sources has been demonstrated in a number of detailed studies of the granite type uranium deposits in this paper. Remarkly the granite-type uranium deposits in Southr China have been shown to have formed from magmatic water, meteoric water, of mixtures of both the above, and origin of waters in the ore-forming fluid may be different for differing uranium deposits ore differing stages of the mineralization. Consequences obtained in this study for typical uranium deposits of different age and geologic sitting agree well with that obtained by other geologic-geochemical investigation. Furthermore, not only meteoric water is of importance to origin and evolution of the ore-forming fluid, but also mixing of waters from different sources is considered to be one of the most characteristic features of many hydrothermal uranium deposits related to granitoids or volcanics. (C.D.G.) [pt

  7. Determination of low concentrations of thorium in granites using X-ray fluorescence technique

    International Nuclear Information System (INIS)

    Shigematsu, H.M.; Sato, I.M.; Iyer, S.S.

    1981-03-01

    An analytical method for the accurate determination of low concentrations of thorium in rocks using X-ray fluorescence technique, was developed. A tungsten tube was utilized for the production of X-rays. The samples were prepared in the form of double layer pressed pellets using boric acid as a binding agent. The concentration of thorium was determined by measuring the intensity of the characteristic first order Th L α line. The calibration was carried out with USGS rock standards AGV-1, GSP-1 and G-2. Seven granite rocks samples from Granite Mountains of Wyoming, USA, supplied by Dr. Stuckless. Also were analysed. The results obtained were compared with values obtained in others laboratories using different analytical methods. The analyses show that the thorium is concentrated in accessory minerals and presented a non-uniform distribution, making sampling an important factor in the analysis of thorium. A discussion of the precision and accuracy of the method is presented. (Author) [pt

  8. Effects of temperature and sliding rate on frictional strength of granite

    Science.gov (United States)

    Lockner, D.A.; Summers, R.; Byerlee, J.D.

    1986-01-01

    Layers of artificial granite gouge have been deformed on saw-cut granite surfaces inclined 30?? to the sample axes. Samples were deformed at a constant confining pressure of 250 MPa and temperatures of 22 to 845??C. The velocity dependence of the steady-state coefficient of friction (??ss) was determined by comparing sliding strengths at different sliding rates. The results of these measurements are consistent with those reported by Solberg and Byerlee (1984) at room temperature and Stesky (1975) between 300 and 400??C. Stesky found that the slip-rate dependence of (??ss) increased above 400??C. In the present study, however, the velocity dependence of (??ss) was nearly independent of temperature. ?? 1986 Birkha??user Verlag.

  9. Speleothem and biofilm formation in a granite/dolerite cave, Northern Sweden

    DEFF Research Database (Denmark)

    Sallstedt, T.; Ivarsson, M.; Lundberg, J.

    2014-01-01

    Tjuv-Antes grotta (Tjuv-Ante's Cave) located in northern Sweden is a round-abraded sea cave ('tunnel cave'), about 30 m in length, formed by rock-water abrasion in a dolerite dyke in granite gneiss. Abundant speleothems are restricted to the inner, mafic parts of the cave and absent on granite...... incorporated remains of microorganisms. Two types of microbial communities can be distinguished associated with the speleothems: an Actinobacteria-like biofilm and a fungal community. Actinobacteria seem to play an important role in the formation of speleothem while the fungal community acts as both...... a constructive and a destructive agent. A modern biofilm dominated by Actinobacteria is present in the speleothem-free parts of the dolerite and located in cave ceiling cracks. These biofilms may represent sites of early speleothem formation. Because of its unusual position in between two types of host rock...

  10. Determination of rare-earth elements content in granitic rocks by argon plasma emission spectrometry

    International Nuclear Information System (INIS)

    Merodio, J.C.; Martinez, J.M.

    1990-01-01

    A method has been developed that enables the rare-earth elements in granitic rocks to be measured sequentially, using an inductively coupled plasma (ICP) source spectrometer with medium spectral resolution (0,02nm). The rocks were dissolved in an open system with a mixture of nitric-hydrofluoric-perchloric acids. Any residues remaining at this stage were removed by filtration and digested using a mini-fusion method with lithium tetraborate. Prior to the excitation in the spectrometer the rare-earth group was separated from other constituents using cation-exchange chromatography. A detailed study of spectral interferences and the evaluation of the detection limits have been performed. Five geochemical reference sample (granitic rocks) were analyzed and the obtained results agree favourably with recommended values and with reported determinations, using high spectral resolution ICP spectrometry. (Author) [es

  11. Assessing the Nation's Coastal Waters....Better

    Science.gov (United States)

    The USEPA has been assessing estuarine and coastal condition in the United States since 1999 via the National Coastal Assessment (NCA) and National Aquatic Resources Surveys (NARS) programs. Approximately 1500 randomly selected coastal sites were surveyed annually during summers ...

  12. COASTAL ANALYSIS FOR Lancaster COUNTY, VIRGINIA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Coastal study as defined in FEMA Guides and Specifications, Appendix D: Guidance for coastal Flooding Analyses and Mapping submitted as a result of a coastal study....

  13. Extreme alkali bicarbonate- and carbonate-rich fluid inclusions in granite pegmatite from the Precambrian Rønne granite, Bornholm Island, Denmark

    Science.gov (United States)

    Thomas, Rainer; Davidson, Paul; Schmidt, Christian

    2011-02-01

    Our study of fluid and melt inclusions in quartz and feldspar from granite pegmatite from the Precambrian Rønne granite, Bornholm Island, Denmark revealed extremely alkali bicarbonate- and carbonate-rich inclusions. The solid phases (daughter crystals) are mainly nahcolite [NaHCO3], zabuyelite [Li2CO3], and in rare cases potash [K2CO3] in addition to the volatile phases CO2 and aqueous carbonate/bicarbonate solution. Rare melt inclusions contain nahcolite, dawsonite [NaAl(CO3)(OH)2], and muscovite. In addition to fluid and melt inclusions, there are primary CO2-rich vapor inclusions, which mostly contain small nahcolite crystals. The identification of potash as a naturally occurring mineral would appear to be the first recorded instance. From the appearance of high concentrations of these carbonates and bicarbonates, we suggest that the mineral-forming media were water- and alkali carbonate-rich silicate melts or highly concentrated fluids. The coexistence of silicate melt inclusions with carbonate-rich fluid and nahcolite-rich vapor inclusions indicates a melt-melt-vapor equilibrium during the crystallization of the pegmatite. These results are supported by the results of hydrothermal diamond anvil cell experiments in the pseudoternary system H2O-NaHCO3-SiO2. Additionally, we show that boundary layer effects were insignificant in the Bornholm pegmatites and are not required for the origin of primary textures in compositionally simple pegmatites at least.

  14. Effect of Compaction Energy on Engineering Properties of Fly Ash –Granite Dust Stabilized Expansive Soil

    OpenAIRE

    Akshaya Kumar Sabat; Ranjan Kumar Moharana

    2015-01-01

    The effects of compaction energy on engineering properties of an expansive soil stabilized with optimum percentage of fly ash-granite dust have been discussed in this paper. Expansive soil stabilized with optimum percentage of fly ash-granite dust was compacted with five compaction energy levels. Maximum dry density and optimum moisture content corresponding to each energy level were determined. Based on these maximum dry density and optimum moisture content, samples were prepared for unco...

  15. Sinking coastal cities

    Science.gov (United States)

    Erkens, Gilles; Bucx, Tom; Dam, Rien; De Lange, Ger; Lambert, John

    2014-05-01

    In many coastal and delta cities land subsidence now exceeds absolute sea level rise up to a factor of ten. Without action, parts of Jakarta, Ho Chi Minh City, Bangkok and numerous other coastal cities will sink below sea level. Land subsidence increases flood vulnerability (frequency, inundation depth and duration of floods), with floods causing major economic damage and loss of lives. In addition, differential land movement causes significant economic losses in the form of structural damage and high maintenance costs. This effects roads and transportation networks, hydraulic infrastructure - such as river embankments, sluice gates, flood barriers and pumping stations -, sewage systems, buildings and foundations. The total damage worldwide is estimated at billions of dollars annually. Excessive groundwater extraction after rapid urbanization and population growth is the main cause of severe land subsidence. In addition, coastal cities are often faced with larger natural subsidence, as they are built on thick sequences of soft soil. Because of ongoing urbanization and population growth in delta areas, in particular in coastal megacities, there is, and will be, more economic development in subsidence-prone areas. The impacts of subsidence are further exacerbated by extreme weather events (short term) and rising sea levels (long term).Consequently, detrimental impacts will increase in the near future, making it necessary to address subsidence related problems now. Subsidence is an issue that involves many policy fields, complex technical aspects and governance embedment. There is a need for an integrated approach in order to manage subsidence and to develop appropriate strategies and measures that are effective and efficient on both the short and long term. Urban (ground)water management, adaptive flood risk management and related spatial planning strategies are just examples of the options available. A major rethink is needed to deal with the 'hidden' but urgent

  16. Musa's granite and Rio Maria's granodiorite Rb/Sr isotopic ages and geochemistry

    International Nuclear Information System (INIS)

    Gastal, M.C.P.; Macambira, M.J.B.; Medeiros, H.; Dall'Agnol, R.

    1987-01-01

    The Musa Granite and the Rio Maria Granodiorite are located at the eastern margin of the Amazonian craton, in the Rio Maria region, where a typical granite-greenstone terrain is characterized. Rb-Sr dating of six samples from different facies of Rio Maria Granodiorite furnished an age of 2564 ± 68 Ma with initial 87 Sr/ 86 Sr radio (IR) of 0.70288 ± 0.00092 (whole rock isochron; 1 ο error; MSWD = 2.26). Thirteen samples from the three facies of Musa Granite (monzogranites, syenogranites and intermediate to felsic hypabyssal rocks) gave Rb-Sr whole rock isochron with an age of 1692 ± 11 Ma and IR of 0.70777 ± 0.00023 (1 ο error, MSWD = 1.89). A preliminary attempt to individualize geochronologically the three facies was done resulting different ages and IRs. There is a coincidence between these ages and the emplacement sequence of these facies of the pluton. The actual meaning of the Rio Maria Granodiorite Rb-Sr age is still uncertain. It could be related to the end of the magmatic crystallization of the batholith as well as to the metamorphic-mylonitic event that affect it. Considering that the Jamon and Musa Granites are petrologically similar that they occur in the same area, it is interesting to note that latter is apparently a little older than the former. The IRs obtained for the two plutons are also not coincident. The isotopic Rb-Sr available data show that the exposed rocks of the Rio Maria Granodiorite have not been able to generate magmas with the compositions of the monzongranitic and the hypabyssal facies of the Musa pluton. On the other hand, rocks isotopically similar to the Rio Maria Granodiorite would theorically be able to generate the Jamon and a magma with the characteristics of the syenogranitic facies of the Musa pluton. (author) [pt

  17. Origin and age of the Eisenkappel gabbro to granite suite (Carinthia, SE Austrian Alps).

    Science.gov (United States)

    Miller, C; Thöni, M; Goessler, W; Tessadri, R

    2011-07-01

    The northern part of the Karawanken plutonic belt is a gabbro-granite complex located just north of the Periadriatic lineament near the Slovenian-Austrian border. Petrographic and geochemical studies of the Eisenkappel intrusive complex indicate that this multiphase plutonic suite developed by a combination of crystal accumulation, fractional crystallization and assimilation processes, magma mixing and mingling. The mafic rocks are alkaline and have within-plate geochemical characteristics, indicating anorogenic magmatism in an extensional setting and derivation from an enriched mantle source. The mafic melts triggered partial melting of the crust and the formation of granite. The granitic rocks are alkalic, metaluminous and have the high Fe/Fe + Mg characteristics of within-plate plutons. Temperature and pressure conditions, derived from amphibole-plagioclase and different amphibole thermobarometers, suggest that the analysed Eisenkappel gabbros crystallized at around 1000 ± 20 °C and 380-470 MPa, whereas the granitic rock crystallized at T ≤ 800 ± 20 °C and ≤ 350 MPa. Mineral-whole rock Sm-Nd analyses of two cumulate gabbros yielded 249 ± 8.4 Ma and 250 ± 26 Ma (εNd: + 3.6), garnet-whole rock Sm-Nd analyses of two silicic samples yielded well-constrained ages of 238.4 ± 1.9 Ma and 242.1 ± 2.1 Ma (εNd: - 2.6).

  18. Engineering Geological Properties of Oil-Contaminated Granitic and Meta sedimentary Soils

    International Nuclear Information System (INIS)

    Zulfahmi Ali Rahman; Umar Hamzah; Noorulakma Ahmad

    2011-01-01

    Hydrocarbon is a light-non aqueous phase liquid or known as LNAPL. It poses environmental hazard if accidentally spilled out into the soil and water systems as a result of its insoluble nature in water. LNAPL component infiltrates into soil through pore spaces and afloat at the top of groundwater level. Some of this hydrocarbon would trap and clog within the voids, difficult to remove and costly to clean. The occurrence of hydrocarbon in the soil definitely degraded the behaviour of soils in terms of engineering properties. This study aimed to investigate the engineering properties of oil-contaminated soil for two different residual soils originally developed from in-situ weathering of granitic and meta sedimentary rocks. The physical characterisations of the soil were determined including particle size distribution, specific gravity test and x-ray diffraction (XRD). The engineering parameters for the contaminated and uncontaminated soils were Atterberg limits, compaction and soil shear strength (UU tests). The amounts of hydrocarbon added to soil were varied at 0 %, 4 %, 8 %, 12 % and 16 % of dried weight of soil samples. The results from the particle size distribution analysis showed that residual soil from granitic rock comprises of 38 % sand, 33 % silt and 4 % clay while meta sedimentary soil consists of 4 % sand, 43 % silt dan 29 % clay. The mean values of specific gravity for the granitic and meta sedimentary soils were 2.56 and 2.61, respectively. The types of minerals present in granitic soil sample were quartz, kaolinite and gibbsite while meta sedimentary soil consists of quartz and kaolinite. The Atterberg limits value decreased as a result of increasing amount of added hydrocarbon into the soil. A similar behavior was observed with the values of maximum dry density and optimum water content with increasing hydrocarbon content. The overall unconsolidated undrained shear strength, C u showed a decreasing trend with the increase in hydrocarbon content

  19. Influence of the properties of granitic rocks on their bioreceptivity to subaerial phototrophic biofilms.

    Science.gov (United States)

    Vázquez-Nion, Daniel; Silva, Benita; Prieto, Beatriz

    2018-01-01

    As any stone substrate is susceptible to biological colonisation, the choice of lithotype used for construction is a key strategy for preventing biodeterioration. For this purpose, a comprehensive evaluation of the primary bioreceptivity to phototrophic biofilms of eleven varieties of granitic rocks, commonly used as building material, was carried out. Blocks were inoculated with a multi-species phototrophic culture and subjected to standardised growth conditions for three months. Biofilm formation was assessed by chlorophyll (chl) fluorescence, colour measurements and extracellular polymeric substances (EPS) quantification. Relationships between the biofilm growth indicators and the properties of the different rocks studied were then analysed. Results showed that the bioreceptivity of the granites is more strongly affected by the physical characteristics of the stones than by their chemical and mineralogical properties, possibly because of the similar composition of the rocks studied. Growth of phototrophic biofilms was enhanced by high open porosity, capillary water content and surface roughness, and the bioreceptivity of weathered granites was higher than that of sound granites. The results obtained can therefore help in the selection of appropriate lithotypes for building purposes. The amounts of EPS produced by subaerial biofilms primarily depended on the requirements and/or characteristics of the biofilm-forming microorganisms, rather than on the bioreceptivity of the substratum, and microorganisms produce the amounts of EPS required at the initial stage of establishment on the stone surface, independently of the subsequent biomass development. These findings are especially important from the point of view of biodeterioration, in which the EPS matrix plays a central role. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Geochemistry of mylonitic tourmaline-bearing granite- gneiss pluton in the northeast of June mine

    Directory of Open Access Journals (Sweden)

    Arezoo Moradi

    2017-07-01

    Full Text Available Introduction Studied mylonitic granite-gneiss body is located in the Northwest of the Azna region in the Lorestan province close to the June dimension stone mine. It is a part of the metamorphic- magmatic complex including granite-gneiss, amphibolite, marble and schist. The crystalline basement is attributed to late-Neoproterozoic and it indicates a Panafrican basement, which yields a laser-ablation ICP–MS U–Pb zircon ages of 608 ± 18 Ma and 588 ± 41 Ma (Shakerardakani et al., 2015. There are two granite-gneiss plutons in the complex that are Galeh– Dezh (Shabanian et al., 2009, and June plutons. The Galeh-Doz pluton are previously proposed as syn-deformation pluton with a major S-shaped bend which has been imparted during dextral shearing with a Late Cretaceous (Mohajjel and Fergusson, 2000. However, new age dating on the pluton using U–Pb in the magmatic zircon produced the late-Neoproterozoic dates (Nutman et al., 2014; Shakerardakani et al., 2015. The granite-gneiss plutons show mylonitic fabrics and microstructures (Shabanian et al., 2010. The geochemical characteristics of mylonitic granite-gneiss body near June mine in NW Azna, is in the focus of our research. Materials and methods Petrographic investigations of 30 thin sections were made. Then eight samples were selected and analyzed for whole rock major, trace and REE compositions by ICP-emission spectrometry and ICP-mass spectrometry using natural rock standards as reference samples for calibration at the ACME Analytical Laboratories in Vancouver, British Columbia, Canada. Results The studied gneiss- granitic body has lepido-granoblastic texture as its major texture. It variably shows evidence of dynamic deformation from ultramylonite to protomylonite. The gneiss- granite consists of quartz, alkali feldspar (mostly as perthite, plagioclase, biotite, white mica (muscovite and phengitic muscovite. Accessory phases in the granitoid include, tourmaline, zircon, magmatic epidote

  1. Laboratory Investigation on Physical and Mechanical Properties of Granite After Heating and Water-Cooling Treatment

    Science.gov (United States)

    Zhang, Fan; Zhao, Jianjian; Hu, Dawei; Skoczylas, Frederic; Shao, Jianfu

    2018-03-01

    High-temperature treatment may cause changes in physical and mechanical properties of rocks. Temperature changing rate (heating, cooling and both of them) plays an important role in those changes. Thermal conductivity tests, ultrasonic pulse velocity tests, gas permeability tests and triaxial compression tests are performed on granite samples after a heating and rapid cooling treatment in order to characterize the changes in physical and mechanical properties. Seven levels of temperature (from 25 to 900 °C) are used. It is found that the physical and mechanical properties of granite are significantly deteriorated by the thermal treatment. The porosity shows a significant increase from 1.19% at the initial state to 6.13% for samples heated to 900 °C. The increase in porosity is mainly due to three factors: (1) a large number of microcracks caused by the rapid cooling rate; (2) the mineral transformation of granite through high-temperature heating and water-cooling process; (3) the rapid cooling process causes the mineral particles to weaken. As the temperature of treatment increases, the thermal conductivity and P-wave velocity decrease while the gas permeability increases. Below 200 °C, the elastic modulus and cohesion increase with temperature increasing. Between 200 and 500 °C, the elastic modulus and cohesion have no obvious change with temperature. Beyond 500 °C, as the temperature increases, the elastic modulus and cohesion obviously decrease and the decreasing rate becomes slower with the increase in confining pressure. Poisson's ratio and internal frictional coefficient have no obvious change as the temperature increases. Moreover, there is a transition from a brittle to ductile behavior when the temperature becomes high. At 900 °C, the granite shows an obvious elastic-plastic behavior.

  2. Evaluation of granite weathering in the Jeroným Mine using non-destructive methods

    Czech Academy of Sciences Publication Activity Database

    Lednická, Markéta; Kaláb, Zdeněk

    2012-01-01

    Roč. 9, č. 2 (2012), s. 211-220 ISSN 1214-9705 R&D Projects: GA ČR GA105/09/0089 Institutional support: RVO:68145535 Keywords : weathering * granite, mine * ultrasonic pulse velocity * Schmidt hammer Subject RIV: DH - Mining, incl. Coal Mining Impact factor: 0.530, year: 2011 http://www.irsm.cas.cz/abstracts/AGG/02_12/10_Lednicka_Kalab.pdf

  3. Stability of cubic zirconia in a granitic system under high pressure and temperature

    International Nuclear Information System (INIS)

    Gibb, F. G. F.; Burakov, B. E.; Taylor, K. J.; Domracheva, Y.

    2008-01-01

    Cubic zirconia is a well known, highly durable material with potential uses as an actinide host phase in ceramic waste forms and inert matrix fuels and in containers for very deep borehole disposal of some highly radioactive wastes. To investigate the behaviour of this material under the conditions of possible use, a cube of ∼2.5 mm edge was made from a single crystal of Yttria stabilized cubic zirconia doped with 0.3 wt.% CeO 2 . The cube was enclosed in powdered granite within a gold capsule and a small amount of H 2 O added before sealing. The sealed capsule was held for 4 months in a cold-seal pressure vessel at a temperature of 780 deg. C and a pressure 150 MPa, simulating both the conditions of a deep borehole disposal involving partial melting of the host rock and the conditions under which the actinide waste form might be encapsulated in granite prior to disposal. At the end of the experiment the quenched, largely glassy, sample was cut into thin slices and studied by optical microscopy, EMPA, SEM and cathodoluminescence methods. The results show that no corrosion of the zirconia crystal or reaction with the granite melt occurred and that no detectable diffusion of elements, including Ce, in or out of the zirconia took place on the timescale of the experiment. Consequently, it appears that cubic zirconia could perform most satisfactorily as both an actinide host waste form for encapsulation in solid granite for very deep disposal and as a container material for deep borehole disposal of highly radioactive wastes (HLW), including spent fuel. (authors)

  4. Doses from radon 222 irradiation for workers of the granite mining industry.

    Science.gov (United States)

    Сrygorieva, L; Tomilin, Yu

    2017-12-01

    determining the integral value of annual effective dose from 222Rn for workers of the granite mining industry and assessment for the expected life effective dose from 222Rn. Materials were the results of measurements of external exposure dose of radiation measurements equiv alent equilibrium volume activity of 222Rn in workrooms and workplaces of major groups of granite quarry workers Mykolaiv region, studies EROA 222Rn air premises of these workers, research content 222Rn in drinking water. Granite quarry workers receive double radiation exposure of 222Rn due to exposure in the workplace and at home. The load in the workplace due to inhalation of 222Rn the air was (2.1 ± 0.2) mSv / year (vari ation 0.9-5.9) in a residential area - (4,1 ± 0,2) mSv/year (variation 1.8-5.9). The total annual effective dose from internal exposure from air flow and working premises and drinking water was on average (6,5 ± 0,2) mSv/year, equal to a maximum value of 20 mSv/year. The expected life for the chronic exposure dose of technological naturally occurring radioactive sources for people who work in the granite quarries and, while living in high risk from radon is in the range of 0.16-1.12 Sv. The research results indicate that in assessing the effects associated with exposure due to radon 222 contingents persons such surveys must take into account all sources of this radionuclide dose. L. Сrygorieva, Yu. Tomilin.

  5. Radiometric evaluation of granite tables in environment public in the city of Recife-PE, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, Edilson A.; Amaral, Romilton dos S.; Santos Junior, Jose A. dos; Bezerra, Jairo D., E-mail: accioly.edilson@ufpe.b, E-mail: romilton@ufpe.b, E-mail: jaraujo@ufpe.b, E-mail: jairo.dias@ufpe.b [Universidade Federal de Pernambuco (RAE/DEN/UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Radioecologia

    2011-07-01

    Granite in Pernambuco has been used as raw-material in several utensils, amongst which, furniture and decoration objects. This granite, besides being traded internally, is also exported to Asia and Europe. Differentiated content of some radionuclides of the ({sup 238}U and {sup 232}Th) and {sup 40}K natural series above average content of other rocks is also commonly found, due to its origin and geological formation. The gamma radiation stems from the decay of the given series, followed by the {sup 40}K, and it should not exceed the 1 mSv.y{sup -1} limit per person of the public, according to the current radiological protection rules (ICRP, 60). This work aimed to radiometrically assess the granite tables used by the public of a well visited restaurant in the city of Recife. It is expected to contribute to the environmental monitoring and to assess the possible health risks for humans. The tables were monitored for a period of about one year. Dosimetric tablets of CaSO{sub 4}:Dy were used. The findings showed doses ranges from the background to 4.7 mSv.y{sup -1}, with general average of dose rate equal to 3.0 mSv.y{sup -1}. Therefore, it was concluded that despite the average dose rates in the different granite objects studied being higher than the recommended rate, the exposure does not offer risks to their users, due to the contact time (meal time) and the levels of radioactive emission found. (author)

  6. An integrated geological, geochemical, and geophysical investigation of uranium metallogenesis in selected granitic plutons of the Miramichi Anticlinorium, New Brunswick

    International Nuclear Information System (INIS)

    Hassan, H.H.; McAllister, A.L.

    1992-01-01

    Integrated geological, geochemical, and geophysical data for the post-tectonic granitic rocks of the North Pole, Burnthill, Dungarvon, Trout Brook, and Rocky Brook plutons and surrounding areas were examined to assess their potential for uranium mineralization. Geological, geochemical, and geophysical criteria that are thought to be useful guides for uranium exploration were also established for the host granites. The granitic plutons were emplaced discordantly, late in the tectonomagmatic sequence and at shallow depths within the metasedimentary rocks of the Miramichi Anticlinorium. Geochemically, the host granites are highly evolved (Si0 2 > 75 wt. %), peraluminous and have strong similarities with ilmenite-series 'S-type' and 'A-type' granitoids. Uranium occurrences are spatially and perhaps temporally associated with late-phase differentiates of the plutons where elevated levels of other lithophile elements such as Sn, W, Mo, and F were also detected. Geophysically, the granitic plutons are associated with distinctively high aeroradiometric eU, eTh, and K anomalies that coincide with strong negative Bouguer anomalies and low magnetic values. Conceptual models involving magmatic and hydrothermal processes have been adopted to explain the concentration of uranium and associated metals in the granitic plutons

  7. Elemental analysis of granite by instrumental neutron activation analysis (INAA) and X-ray fluorescence analysis (XRF).

    Science.gov (United States)

    El-Taher, A

    2012-01-01

    The instrumental neutron activation analysis technique (INAA) was used for qualitative and quantitative analysis of granite samples collected from four locations in the Aswan area in South Egypt. The samples were prepared together with their standards and simultaneously irradiated in a neutron flux of 7×10(11)n/cm(2)s in the TRIGA Mainz research reactor. Gamma-ray spectra from an hyper-pure germanium detector were analyzed. The present study provides the basic data of elemental concentrations of granite rocks. The following elements have been determined Na, Mg, K, Fe, Mn, Sc, Cr, Ti, Co, Zn, Ga, Rb, Zr, Nb, Sn, Ba, Cs, La, Ce, Nd, Sm, Eu, Yb, Lu, Hf, Ta, Th and U. The X-ray fluorescence (XRF) was used for comparison and to detect elements, which can be detected only by XRF such as F, S, Cl, Co, Cu, Mo, Ni, Pb, Se and V. The data presented here are our contribution to understanding the elemental composition of the granite rocks. Because there are no existing databases for the elemental analysis of granite, our results are a start to establishing a database for the Egyptian granite. It is hoped that the data presented here will be useful to those dealing with geochemistry, granite chemistry and related fields. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Technical support for GEIS: radioactive waste isolation in geologic formations. Volume 5. Baseline rock properties-granite

    International Nuclear Information System (INIS)

    1978-04-01

    This volume, Y/OWI/TM-36/5, Baseline Rock Properties--Granite, is one of a 23-volume series, ''Technical Support for GEIS: Radioactive Waste Isolation in Geologic Formations, Y/OWI/TM-36'' which supplements a ''Contribution to Draft Generic Environmental Impact Statement on Commercial Waste Management: Radioactive Waste Isolation in Geologic Formations, Y/OWI/TM-44.'' The series provides a more complete technical basis for the preconceptual designs, resource requirements, and environmental source terms associated with isolating commercial LWR wastes in underground repositories in salt, granite, shale and basalt. Wastes are considered from three fuel cycles: uranium and plutonium recycling, no recycling of spent fuel and uranium-only recycling. This report, on the rock properties of typical granites, includes an evaluation of the various test results reported in the literature. Firstly, a literature survey was made in order to obtain a feel for the range of rock properties encountered. Then, granites representative of different geologic ages and from different parts of the United States were selected and studied in further detail. Some of the special characteristics of granite, such as anisotropy, creep and weathering were also investigated. Lastly, intact properties for a typical granite were selected and rock mass properties were derived using appropriate correction factors

  9. Predicted indoor radon concentrations from a Monte Carlo simulation of 1 000 000 granite countertop purchases

    International Nuclear Information System (INIS)

    Allen, J G; Zwack, L M; MacIntosh, D L; Minegishi, T; Stewart, J H; McCarthy, J F

    2013-01-01

    Previous research examining radon exposure from granite countertops relied on using a limited number of exposure scenarios. We expanded upon this analysis and determined the probability that installing a granite countertop in a residential home would lead to a meaningful radon exposure by performing a Monte Carlo simulation to obtain a distribution of potential indoor radon concentrations attributable to granite. The Monte Carlo analysis included estimates of the probability that a particular type of granite would be purchased, the radon flux associated with that type, the size of the countertop purchased, the volume of the home where it would be installed and the air exchange rate of that home. One million countertop purchases were simulated and 99.99% of the resulting radon concentrations were lower than the average outdoor radon concentrations in the US (14.8 Bq m −3 ; 0.4 pCi l −1 ). The median predicted indoor concentration from granite countertops was 0.06 Bq m −3 (1.59 × 10 −3 pCi l −1 ), which is over 2000 times lower than the US Environmental Protection Agency’s action level for indoor radon (148 Bq m −3 ; 4 pCi l −1 ). The results show that there is a low probability of a granite countertop causing elevated levels of radon in a home. (paper)

  10. Microstructures and rheology of the shear zones in granite Marmarajá, Lavalleja Province, Uruguay

    International Nuclear Information System (INIS)

    Scaglia, F.; Paris, A.

    2010-01-01

    The study area (coordinates x : 567 , x : 577.7 , y: 6216 : and ' : 6225 km ) is located near the town of Marschallin (Department of Lavalleja). It is represented mostly by granite, deformed granites and quartzite mylonites , whereas amphibolites and volcanic breccias are of small size . The Marmarajá (biotite - monzogranite) batholith, considered to post- orogenic tardi occupies about 80% of the study area , and is fragmented into three sectors per kilometer mylonitic belts by the SW- NE direction. The deformed granite is located west and east of the study area forming an extensive parallel on both sides of the mylonite belt. The mylonites are in topographic low along which the major waterways of the narrow belts direction N50E and dips 40 ° -50 ° to the area SE with thicknesses of up to 1km and lengths of tens of kilometers continuously , north and south of the area study. These belts have similar directions mylonitic the Sierra megatranscurrencia whale and may be contemporaneous to it. In turn, the kinematic indicators suggest sinistral sense justifying further similarity to the previous one. Major fractures have three orientations: N15E ; Vertical to subvertical N64E and N45W ( approx. 80 °). Based on studies of the lithologies petrographic areas of low deformation and is relieved areas of moderate to high strain, each having typical microstructures of ductile deformation (greater than 400 ° C )

  11. The search for the youngest granites in the southern part of the Natal Metamorphic Province

    International Nuclear Information System (INIS)

    Thomas, R.J.; Eglington, B.M.

    1990-01-01

    It is clear that the Belmont Pluton and the dykes are geochemically, isotopically and therefore, genetically distinct. The Belmont pluton is probably related to the garnet leucogranite phase of the Margate Complex. It is suggested that the dykes (∼ 965 Ma) are younger than the Belmont pluton (∼1055 Ma). The relatively low initial 87 Sr/ 86 Sr are typical of the granites intruded at ∼1000 Ma. The age of the dykes is comparable with the 951 ± 16 Ma (R o =.70320 ± 13) given for the Sezela pluton. The high R o (∼0.715) of the dykes is similar to other, minor granite sheets from southern Natal, and is compatible with an origin by late-stage melting of pre-existing radiogenic material. Both the dykes and the Sezela pluton are unequivocally younger than the D 3 deformation, whereas the young dates from the Oribi Gorge Suite are controversial. Thus, although it is possible that some of the minor, intrusive granitic sheets could yet be shown to be of Pan-African age, it is evident that no significant Pan-African magmatism or thermal overprinting has affected the Natal sector of the Namaqua-Natal-Maudheim belt. 1 fig., 7 refs

  12. Hydric properties of some iberian ornamental granites with different superficial finishes: a petrophysical interpretation

    Directory of Open Access Journals (Sweden)

    Rojo, A.

    2003-03-01

    Full Text Available Some physical properties of three ornamental granites with different superficial finishes (polished, sawn and flamed were quantified by standard tests. These granites are commercially known as Rosa Porrino, Rosavel and Blanco Alcazar. The determined properties were: density, open porosity, water absorption, capillarity, evaporation, vapour absorption and water vapour permeability. The values of the hydric properties in the studied granites fundamentally depended on their textural characteristics, mainly grain size, micro cracking network and open porosity, and, to a lesser extent, on their superficial finish.

    El estudio analiza las diferencias en el comportamiento hídrico de tres granitos con diferentes acabados superficiales: pulido, corte de sierra y chorro de fuego. Estos granitos se comercializan con los nombres de Rosa Porrino, Rosavel y Blanco Alcázar. Las propiedades determinadas han sido: densidad, porosidad abierta, absorción libre de agua, absorción de vapor de agua, absorción de agua por capilaridad, evaporación y permeabilidad al vapor de agua. Los valores de las propiedades hídricas determinadas dependen fundamentalmente de las características texturales: tamaño de grano, microfisuras y porosidad abierta y, en menor medida, de los acabados superficiales.

  13. A study of selenium and tin sorption on granite and goethite

    International Nuclear Information System (INIS)

    Ticknor, K.V.; McMurry, J.

    1996-01-01

    Sensitivity analyses based on an illustrative performance assessment case study of a disposal concept for nuclear fuel waste have shown that radioisotopes of Se and Sn could have a significant effect on cumulative radioactive dose if they were to be transported through the geosphere without retardation. Static batch sorption methods, coupled with 2 n factorial experimental designs, were used to determine the extent to which Se and Sn can be sorbed by granite and goethite as a function of total dissolved solids concentration, (TDS), natural fulvic acid concentration as dissolved organic carbon, [DOC], pH and, for the studies with Se, the Se concentration, [Se]. Aqueous speciation and the saturation indices of solubility-controlling solid phases were estimated using the speciation code HARPHRQ with the HATCHES thermodynamic database. The experimental results indicated that Se sorption on granite was low and not affected by changes in [DOC] or [TDS]. Increased [Se] and increased pH decreased sorption. For Se sorption on goethite, the pH range was narrow but indicated that sorption decreased as pH increased. Increased [TDS] and [Se] lowered sorption on goethite, but changes in (DOC] had no effect on sorption. For Sn, increased pH, [TDS] and [DOC] decreased sorption on granite. For Sn sorption on goethite, increased [DOC] resulted in decreased sorption, but differences in [TDS] and pH had little consistent effect on sorption. (author)

  14. A study of selenium and tin sorption on granite and geothite

    International Nuclear Information System (INIS)

    Ticknor, K.V.; McMurry, J.

    1996-01-01

    Sensitivity analyses based on an illustrative performance assessment case study of a disposal concept for nuclear fuel waste have shown that radioisotopes of Se and Sn could have a significant effect on cumulative radioactive dose if they were to be transported through the geosphere without retardation. Static batch sorption methods, coupled with 2 n factorial experimental designs, were used to determine the extent to which Se and Sn can be sorbed by granite and goethite as a function of total dissolved solids concentration, [TDS], natural fulvic acid concentration as dissolved organic carbon, [DOC], pH and, for the studies with Se, the Se concentration, [Se]. Aqueous speciation and the saturation indices of solubility-controlling solid phases were estimated using the speciation code HARPHRQ with the HATCHES thermodynamic database. The experimental results indicated that Se sorption on granite was, low and not affected by changes in [DOC] or [TDS]. Increased [Se] and increased pH decreased sorption. For Se sorption on goethite, the pH range was narrow but indicated that sorption decreased as pH increased. Increased [TDS] and [Se] lowered sorption on goethite, but changes in [DOC] had no effect on sorption. For Sn, increased pH, [TDS] and [DOC] decreased sorption on granite. For Sn sorption on goethite, increased [DOC] resulted in decreased sorption, but differences in [TDS] and pH had little consistent effect on sorption. (orig.)

  15. Characterization of cesium diffusion behavior into granite matrix using Rutherford backscattering spectrometry

    Science.gov (United States)

    Tsai, Shih-Chin; Lee, Chuan-Pin; Tsai, Tsuey-Lin; Yu, Yueh-Chung

    2017-10-01

    The characterization of radionuclide diffusion behavior is necessary for performance assessment of granite as a geological barrier for high-level radioactive waste disposal. Rutherford backscattering spectrometry (RBS), a novel nuclear ion-beam technique, was selected in this study because it is suitable for analyzing the concentration gradients of heavy elements in a well-defined matrix and allows measuring diffusion coefficients on a micrometer scale. In this study Cs was selected to represent Cs-135 (a key radionuclide in high-level waste) diffusion in granite. The Cs energy spectrum and concentration deep profile were analyzed and the diffusion coefficient of Cs in granite for three different locations were determined, which were 2.06 × 10-19m2 s-1, 3.58 × 10-19m2 s-1, and 7.19 × 10-19m2 s-1-19m2 s-19m2 s-1, respectively, which were of a similiar order of magnitude. Results from other studies are also compared and discussed in this paper.

  16. Retention and radionuclide migration mechanisms in the environment of a radioactive waste repository in granitic formation

    International Nuclear Information System (INIS)

    Rancon, D.; Miara, P; Vinson, J.M.; Petronin, J.C.; Dozol, J.F.

    1986-01-01

    A laboratory pre-determination of retention mechanisms of radionuclides migrating outside the primary waste containers in repository surroundings was started up. Backfillings materials (clay and sand) as well as granite and its weathering products are concerned here. A method allowing the evaluation of the sorption and desorption of radionuclides of the surfaces of fractures by measuring surface retention coefficients, had initially been started up as well as a laboratory device developed for experiments in a reducing environment. The experiments have consisted of studying the sorbing properties of granite minerals of Auriat and its weathering products and of determining the retention of Np, Pu, AM, CS and Sr on the surface fractures of this granite. The influence of a reducing environment on the behaviour of activities has been studied. Complementary percolation tests have also been carried out on clays, at raised temperature and under irradiation. These experiments have enabled a deeper knowledge of retention mechanisms, the taking of parametric sensitivity measurements and the preparation of elaborating more performing experimental devices which included the parameters needed for a realistic simulation of transfer phenomena

  17. Gas chromatography applied to cultural heritage. Analysis of dark patinas on granite surfaces.

    Science.gov (United States)

    Aira, N; Jurado, V; Silva, B; Prieto, B

    2007-04-13

    The formation of dark patinas has been mainly related with deposition of gases and particles, and sulphation mechanisms particularly in calcareous rocks. However, in granitic monuments located in Galicia (northwest of Spain), especially in rural areas, this origin is unlikely since granite is a very poor calcium-containing rock and the atmospheric pollution in this area is negligible. A biological origin seems to be most probable. In order to know the importance of biological and atmospheric factors in the formation of dark patinas on granitic monuments, a number of analyses using several techniques are needed. The characterization of fatty acids in patinas by gas chromatography has established clear differences among samples. Thus, all of the samples having a biological origin displayed a similar fatty acid pattern, with unsaturated fatty acids predominating, especially oleic and linoleic acids; these were followed in abundance by the branched fatty acid 18:00 anteiso, and palmitic acid. Different patterns of fatty acid allowed establishment of an anthropogenic origin of the some of the patinas analysed.

  18. Mechanisms of hydrothermal alteration in a granitic rock. Consequences for high-level radioactive waste disposal

    International Nuclear Information System (INIS)

    Parneix, J.C.

    1987-06-01

    The study of hydrothermal alteration in the Auriat granitic rock (France, Massif-Central) has evidenced three main events: - a pervasive chloritisation of biotites in some parts of the drill-core, - an alteration localized around subvertical cracks and superimposed on previously chloritized or unaltered granite, - an alteration localized around subhorizontal cracks cross-cutting the preceding ones. The second type of alteration, produced by a geothermal system, gives the most interesting results to be applied to the nuclear radwaste disposal problem. Among primary minerals of granite, only biotite (or chlorite) and oligoclase are intensively altered. Therefore, the chemical composition of these minerals induces the nature of secondary parageneses. These, associated to the subvertical cracks network, indicate a thermal gradient of 150 C/Km. The geochemical code has allowed to corroborate that the thermal gradient was responsible for the occurrence of different parageneses with depth. Moreover, it was shown that the variable mineralogy around cracks was due to a thermal profile established at equilibrium between the rock and the fluid. Therefore, the extent of the alteration was proportional to the thermal power of the fluid. A dissolution and next a precipitation phase of new minerals characterize hydrothermal alteration, which is due to the thermal power emitted by radioactive waste and linked with the evolution of temperature during time. This alteration provokes two favourable events to storage: decrease of rock porosity and increase of sorption capacity [fr

  19. Natural analogue and microstructural studies in relation to radionuclide retardation by rock matrix diffusion in granite

    International Nuclear Information System (INIS)

    Montoto, M.; Rodriguez Rey, A.; Ruiz de Argandona, V.G.; Calleja, L.; Menendez, B.

    1992-01-01

    The possibility that radionuclide retardation by rock matrix diffusion will be limited in granitic rocks by geological factors is studied, as well as the possibility that diffusion will be confined to a narrow zone from water-conducting fractures. Petrophysical measurements, uranium series and geochemical analyses in the rock adjacent to fractures, have been performed to establish the extent of fracture-related microstructural changes that might influence the potential for diffusion and whether or not there is any record of diffusion of uranium, its daughters, or other elements. The results obtained from El Berrocal (Spain), Stripa (Sweden) and White-shell (Canada) granites, suggest that: (a) there is a zone adjacent to the fractures (generally less than 100 mm) where microstructural changes and enhanced uranium mobility exist; (b) the evidence for diffusion having taken place in the rock is confined largely to this zone. So, it appears that diffusivity determinations on rock collected away from the influence of fractures will not give representative data for diffusion modelling, in addition to the effect of distressing after removing rocks from depth. It is suggested that diffusion will be of limited effectiveness as a retardation mechanism in many granitic rocks, particularly in water movement confined to narrow channels where access by nuclides to the fracture walls is restricted. 51 refs., 56 figs., 9 tabs., 9 appendices

  20. Southern complex: geology, geochemistry, mineralogy, and mineral chemistry of selected uranium- and thorium-rich granites

    International Nuclear Information System (INIS)

    Hoffman, M.A.

    1987-01-01

    Four major rock groups are defined in the Southern Complex: the Bell Creek Granite (BCG), the Clotted Granitoids (CGR), the Albite Granite (AGR), and the Migmatite Complex. Metatexites of the Migmatite Complex are the oldest rocks and include paleosome of a metasedimentary and metavolcanic protolith represented by Banded Iron Formation, Banded Amphibolite, and Banded Gneisses, and interlayered or crosscutting leucogranites. The CGR span the range from metatexite to diatexite and represent in-situ partial melting of metapelitic layers in the protolith during intrusion of the BCG. The BCG cuts the migmatites, is locally cut by the CGR, and was derived by partial melting of a dominantly metasedimentary protolith at some depth below the presently exposed migmatites during a regional tectonothermal event. The Albite Granite is a 2km diameter, muscovite-fluorite-columbite-bearing intrusive stock that cuts all other major units. The thorium history of the BCG is a function of the history of monazite. The thorium history of the CGR is also dominated by monazite but the thorium content of this unit cannot be entirely accounted for by original restite monazite. The uranium history of the BCG and CGR was dominated by magmatic differentiation and post magmatic, metamorphic and supergene redistributions and is largely independent of the thorium history. The thorium and uranium history of the AGR was dominated by magmatic/deuteric processes unlike the BCG and CGR

  1. Laser cleaning of graffiti in Rosa Porriño granite

    Science.gov (United States)

    Fiorucci, M. P.; Lamas, J.; López, A. J.; Rivas, T.; Ramil, A.

    2011-05-01

    This paper presents preliminary results in determining the optimum parameters for graffiti removal in a ornamental granite, Rosa Porriño, by means of Nd:YVO4 laser at the wavelength of 355 nm and different fluences. The spray-paints (black, blue, red and silver) tested in this work were chemically characterized by means of elemental analysis, XRF, SEM/EDX and FTIR. The assessment of cleaning and characterization of the stone substrate before and after irradiation was performed by means of optical microscopy, SEM-EDX, and confocal microscopy. The analysis of the irradiated samples showed in some cases, damage in the granite substrate associated to thermal effects. The severity and kind of damage, depends on the laser fluence delivered, the constituent mineral irradiated, and the color used to paint the stone. So, at the highest levels of fluence the laser beam is able to scratch the surface, being the depth of the grooves in the stone measured by confocal microscopy. Moreover, SEM images show the differential damage caused in mineral constituents of granite i.e., quartz, feldspars, and biotite, the latter providing to be the most affected mineral, reaching melting even at low levels of fluence. It was appreciated that the color of the spray-paint affects the results of cleaning, and observed differences could be attributed to different organic constituents in the paints or the presence of metallic particles in its composition, as occurs with silver paint.

  2. Inclusive development and coastal adaptiveness

    NARCIS (Netherlands)

    Gupta, J.; Bavinck, M.

    Highlights •The problems of demographic concentration and climate change result in an appeal for new coastal governance strategies. •Much of the coastal zone management literature tends to take a technocratic, growth-oriented focus. •A technocratic, growth-oriented focus exacerbates the poor's

  3. Integrated coastal management in Uruguay

    International Nuclear Information System (INIS)

    2011-01-01

    Integrated coastal management in Uruguay Carmelo includes the following areas-Nueva Palmira challenges and opportunities for local development in a context of large-scale industrial (Conchillas Uruguay), coastal management and stream Arroyo Solis Solis Chico Grande, Punta Colorada and Punta Negra, Maldonado Province Arroyo Valizas and sustainable tourism.

  4. "Petit Granit": a Belgian limestone used in heritage, construction and sculpture.

    Science.gov (United States)

    Pereira, Dolores; Touneur, Francis; Bernáldez, Lorenzo; García Blázguez, Ana

    2014-05-01

    "Petit Granit" is a Lower Carboniferous (Tournaisian) grey-bluish crinoidal limestone that becomes shiny black when polished. The rock is known under several other names like Pierre Bleue (Blue Stone), but at the same time it should not be confused with other natural stones having a similar commercial name (e.g. Chinese Bluestone or Irish Bluestone) which are superficially similar limestones. It consists of around 96% microcrystalline calcite and a high proportion of fossils, mainly crinoids. In addition some dolomite, quartz, pyrite, marcasite and fluorite are present. Around fifteen quarries are active these days, employing almost one thousand people and thus is an important part of the natural stone economy in Belgium. "Petit Granit" has an Appellation d'Origine Locale (Local Appellation of Origin) designation since 1999. It has been extracted in several regions of South Belgium since the Middle Ages. In a sense the name is misleading because it is not an igneous rock and therefore not a true granite, but it derives from the profusion of numerous white fossil fragments in a dark carbonaceous matrix which look similar to feldspar crystals in a granitic background. The stone characterizes many façades of the urban architecture of Brussels and other Belgian cities, and since the second half of the 19th century it has been used in various countries in Europe and overseas. Its high density and uniformity mean that it takes an excellent polish and thus has versatile use as a dimension stone. "Petit Granit" has also been used widely in sculpture and architecture by several well known artists (e.g. Mateo Hernández, Michel Smolders, Tom Blatt, Elise Delbrassinne, Benoît Luyckx, Santiago Calatrava, among others). However, deterioration has been observed when it has been used for exterior purposes, and appropriate measures need to be taken to prevent this. This stone can be considered as Global Heritage Stone Resource in Europe, for both its use in construction and for

  5. The correlation between selenium adsorption and the mineral and chemical composition of Taiwan local granite samples

    International Nuclear Information System (INIS)

    Wang, TsingHai; Chiang, Chu-Ling; Wang, Chu-Fang

    2015-01-01

    Selenium-79 (Se-79) is a radioactive isotope of selenium, which is considered as one of the highly mobile nuclides since Se-79 would be presented in an anion species when dissolving into the intruded groundwater. Being an anionic species, the transport of Se-79 would be regulated by the metal oxides relevant minerals such as goethite and hematite (Jan et al., 2008). This is true that the transport of selenium in the shallow surface environment could be relatively easy to estimate by considering the amount of these metal oxides presenting in the soils and sediments. However, when dealing with deep geological repository, the transport of Se-79 becomes less predictable because of the much less content of metal oxide residing in the host rock such as granite. In order to conduct a reliable performance assessment of repository, it is very important to establish the correlation between selenium adsorption and the properties of potential host rock, in this study, the mineral and chemical compositions of Taiwan local granite. From this point of view, selenium adsorption experiments were conducted with 54 different Taiwan local granite samples collected from the depth ranging from 100 ∝ 400 meters below the surface. These granite samples represent a variety of deep geological environments, including the intact rock, groundwater intruded zones, and some weathered samples. Based upon our preliminary results, several solid conclusions could be made. First, the correlation coefficients between the Kd values and the mineral and chemical compositions are rather low (R-square values are often < 0.2). This points out the complexity of these geological samples and strongly suggests more efforts should be put into to acquire more relevant information. Second, the correlation between the selenium Kd values and the content of iron oxide (R-square 0.110) is much higher than that between the CEC of these granite samples (R-square 0.001). This clearly indicates that the minerals that

  6. Origin of allanite in gneiss and granite in the Dabie orogenic belt, Central East China

    Science.gov (United States)

    Guo, Haihao; Xiao, Yilin; Xu, Lijuan; Sun, He; Huang, Jian; Hou, Zhenhui

    2017-03-01

    Allanite is a common accessory mineral phase, representing an important carrier of rare earth elements, Th, U, Sr and other trace elements in most continental rocks. As Th and U can be incorporated into the allanite lattice, the mineral is a good geochronological tool for constraining geological events. Moreover, the trace element features δEu, Th/U ratio and common lead content of allanite are indicators of the forming conditions. Allanite and coexisting epidote-group minerals are abundant in ultrahigh-pressure (UHP) metamorphic rocks from the Dabie-Sulu orogen in central East China. However, if these minerals formed in the Neoproterozoic as magmatic phases, or in the Triassic as metamorphic phases is a matter of long-standing controversy. We report major and trace element analyses of whole rocks, allanite and coexisting epidote-group minerals, together with U-Th-Pb isotopic compositions of allanite in UHP gneiss from the Dabie-Sulu orogen, and allanite in the adjacent Jingshan granite. The granite is emplaced along the southeastern margin of the North China Craton and considered a product of partial melting of the subducted Dabie-Sulu gneiss. Trace elements (low Th/U and La/Sm, high δEu and high Sr) and high common lead concentrations indicate a metamorphic origin of allanite-epidote in the UHP gneiss. On the other hand, coarse-grained allanite from the Jingshan granite shows a corrosion core and a magmatic rim with common 208Pb up to 70% in the core and less than 30% in the rim. The allanite cores are of peritectic and the rims of magmatic origin with ages of ∼160 Ma, consistent with the granite crystallization age. In combination with previous studies, we conclude that the allanite of the Jingshan granite has form from the subducted and remolten Dabie-Sulu gneiss. Allanite records Triassic UHP metamorphic ages as well as Jurassic peritectic-magmatic ages as a part of the evolution of the Dabie-Sulu orogen.

  7. Fertility of Rare-Metal Peraluminous Granites and Formation Conditions of Tungsten Deposits

    Science.gov (United States)

    Syritso, L. F.; Badanina, E. V.; Abushkevich, V. S.; Volkova, E. V.; Terekhov, A. V.

    2018-01-01

    The tungsten distribution in rocks of the Kukulbei Complex in eastern Transbaikal region results in a high potential of rare-metal peraluminous granites (RPG) for W mineralization and displays a different behavior of W in Li-F and "standard" RPG. These subtypes differ in the behavior of W in melt, spatial localization of mineralization, and the timing of wolframite crystallization relative to the age of the parental granitic rocks. The significant of W concentration is assumed to be due to fractionation of the Li-F melt; however, wolframite mineralization in Li-F enriched granite is not typical in nature. The results of experiments and our calculations of W solubility in granitic melt show that wolframite hardly ever crystallizes directly from melt; it likely migrates in the fluid phase and is then removes from the magma chamber to the host rocks, where secondary concentration takes place in exocontact greisens and quartz-cassiterite-wolframite veins. At the same time, the isotopic age of accessory wolframite (139.5 ± 2.1 Ma) within the Orlovka massif of Li-F granite is close to the formation age of the massif (140.6 ± 2.9 Ma). A different W behavior is recorded in the RPG subtype with a low lithium and fluorine concentration, exemplified by the Spokoininsky massif. There is no significant W gain in the melt. All varieties of wolframite mineralization in the Spokoininsky massif are derived from greisens, veins, and pegmatoids yielding the same crystallization ages (139.5 ± 1.1 Ma), which are 0.9-1.8 Ma later (taking into account the mean-square weighted deviation) than the Spokoininsky granite formation (144.5 ± 1.4 Ma). Perhaps this period corresponds to the time of transition from the magmatic stage to hydrothermal alteration. Comparison of the isotope characteristics (Rb-Sr and Sm-Nd isotope systems) of rocks and the associated ore minerals (wolframite, cassiterite) from all examined deposits shows a depletion in ɛNd values for ore minerals relative to the

  8. Interpretation of airborne geophysical data over the Aarons Pass Granite, near Mudgee NSW

    International Nuclear Information System (INIS)

    Purss, M.

    1998-01-01

    Aeromagnetic and airborne radiometric data from the National Geoscience Mapping Accord (courtesy of the Australian Geological Survey Organisation and the New South Wales Department of Mineral Resources) for the southern portion of the Mudgee 1:100,000 Sheet, together with gravity data from the Australian National Gravity Database (courtesy of the Australian Geological Survey Organisation) were interpreted to aid in solving geological problems highlighted by previous studies of the Aarons Pass Granite. Of these, the western margin of the granite (postulated as being fault related) and an unusual radiometric anomaly were the main focuses of study. Interpretation of the aeromagnetic and airborne radiometric data involved the application of numerous filters and image display formats in order to identify spatial correlation's within and between the respective data. The aeromagnetic, or total magnetic intensity (TMI), data were represented as pseudocolour and intensity layers, with a directional sun-angle illumination algorithm applied to the intensity layer. 'High pass' and 'upward continuation' filters were also applied to the data. The airborne radiometric data were examined by various means. Firstly, each of the potassium, thorium, and uranium bands were normalised against the total counts band and represented as pseudocolour layers draped over sun-angle illuminated intensity layers. Secondly, in the standard potassium, thorium, and uranium (Red, Green, Blue) ternary image format, as a flat RGB image and an RGB image draped over a sun-angle illuminated high pass filtered TMI layer. And thirdly, as a K/Th ratio image in pseudocolour draped over a sun-angle illuminated intensity layer. Although the gravity data were not collected by airborne means it nonetheless proved useful in highlighting important spatial information relating to the western margin of the granite which was obscured by the nature of the aeromagnetic data. As a result, the image analysis of this data

  9. The Lagoa Real subalkaline granitic complex (south Bahia, Brazil): a source for uranium mineralizations associated with Na-Ca metasomatism

    International Nuclear Information System (INIS)

    Maruejol, P.; Cuney, M.; Poty, B.; Neto, A.M.

    1987-01-01

    In the central zone of the Sao Francisco Craton (South Bahia), the lower Proterozoic Lagoa Real granites and orthogneisses overthrust to the West the younger Urandi and Espinhaco metamorphic series, probably a late Brazilian event. This thrust is related to the regional metamorphism (amphibolite facies) of the Lagoa Real granites and induces a reverse HP metamorphism in the over thrusted series. Undeformed granites (sao Timoeto type) present two feldspars, perthitic orthoclase largely predominant over plagioclase (oligoclase ≥ albite), blue quartz, Fe-rich amphibole and biotite ± clinopyroxene assemblages, ilmenite ≥ magnetite, zircon, apatite, allanite and Nb ± Ti-REE oxides and silicates. The crystallization of the granites begins at high temperature and under low fO 2 and P H2O conditions. Fractional crystallization of pyroxene and plagioclase leads to silica enrichment during magmatic differentiation. Increasing fO 2 and P H2O are observed during this evolution. Orthogneisses show strongly recrystallized paragenesis: equal abundance of non-perthitic microcline and plagioclase (oligoclase ≤ albite), quartz, more Al-rich amphibole and biotite, magnetite, sphene, zircon, allanite, Nb ± Ti-REE oxides and silicates, and ± apatite. HT Na and Ca metasomatism occurs 330 Ma later than granite emplacement and is synchronous with important uranium mineralizations. Major elements and trace-elements geochemistry of the granites and orthogneisses indicate subalkaline to alkaline typology. Incompatible behaviour of Th, REE, Y, Zr, Nb, and F points out a convergence with alkaline magmatism. CI, F, Th, Y, REE, NB enrichments and Ba, Sr depletions are also related to a late magmatic stage. U-Th-rich and metamict accessory minerals of the granites represent a favorabl source for the Lagoa Real uranium ore-deposits [pt

  10. The Influence of Temperature on Time-Dependent Deformation and Failure in Granite: A Mesoscale Modeling Approach

    Science.gov (United States)

    Xu, T.; Zhou, G. L.; Heap, Michael J.; Zhu, W. C.; Chen, C. F.; Baud, Patrick

    2017-09-01

    An understanding of the influence of temperature on brittle creep in granite is important for the management and optimization of granitic nuclear waste repositories and geothermal resources. We propose here a two-dimensional, thermo-mechanical numerical model that describes the time-dependent brittle deformation (brittle creep) of low-porosity granite under different constant temperatures and confining pressures. The mesoscale model accounts for material heterogeneity through a stochastic local failure stress field, and local material degradation using an exponential material softening law. Importantly, the model introduces the concept of a mesoscopic renormalization to capture the co-operative interaction between microcracks in the transition from distributed to localized damage. The mesoscale physico-mechanical parameters for the model were first determined using a trial-and-error method (until the modeled output accurately captured mechanical data from constant strain rate experiments on low-porosity granite at three different confining pressures). The thermo-physical parameters required for the model, such as specific heat capacity, coefficient of linear thermal expansion, and thermal conductivity, were then determined from brittle creep experiments performed on the same low-porosity granite at temperatures of 23, 50, and 90 °C. The good agreement between the modeled output and the experimental data, using a unique set of thermo-physico-mechanical parameters, lends confidence to our numerical approach. Using these parameters, we then explore the influence of temperature, differential stress, confining pressure, and sample homogeneity on brittle creep in low-porosity granite. Our simulations show that increases in temperature and differential stress increase the creep strain rate and therefore reduce time-to-failure, while increases in confining pressure and sample homogeneity decrease creep strain rate and increase time-to-failure. We anticipate that the

  11. Nearly contemporaneous evolution of the A- and S-type fractionated granites in the Krušné hory/Erzgebirge Mts., Central Europe

    Czech Academy of Sciences Publication Activity Database

    Breiter, Karel

    2012-01-01

    Roč. 151, 15 October (2012), s. 105-121 ISSN 0024-4937 R&D Projects: GA AV ČR IAA300130801; GA ČR GAP210/10/1105 Keywords : A-type granite * Bohemiam Massif * Erzgebirge * granite classification * Krušné hory Mts. * S-type granite Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.779, year: 2012

  12. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam; Smolt Monitoring by Federal and Non-Federal Entities, 2001-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Putnam, Scott A.

    2003-06-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon smolts O. nerka during the 2001 spring out-migration at migrant traps on the Snake River and Salmon River. In 2001 fish management agencies released significant numbers of hatchery chinook salmon and steelhead trout above Lower Granite Dam that were not marked with a fin clip or coded-wire tag. Generally, these fish were distinguishable from wild fish by the occurrence of fin erosion. Total annual hatchery chinook salmon catch at the Snake River trap was 11% of the 2000 numbers. The wild chinook catch was 3% of the previous year's catch. Hatchery steelhead trout catch was 49% of 2000 numbers. Wild steelhead trout catch was 69% of 2000 numbers. The Snake River trap collected 28 age-0 chinook salmon. During 2001 the Snake River trap captured zero hatchery and zero wild/natural sockeye salmon and six hatchery coho salmon O. kisutch. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with flow. The significant reduction in catch during 2001 was due to a reduction in hatchery chinook production (60% of 2000 release) and due to extreme low flows. Trap operations began on March 11 and were terminated on June 29. The trap was out of operation for a total of two days due to mechanical failure or debris. Hatchery chinook salmon catch at the Salmon River trap was 47% and wild chinook salmon catch was 67% of 2000 numbers. The hatchery steelhead trout collection in 2001 was 178% of the 2000 numbers. Wild steelhead trout collection in 2001 was 145% of the previous year's catch. Trap operations began on March 11 and were terminated on June 8 due to the end of the smolt monitoring season. There were no days where the trap was out of operation due to high flow or debris. The decrease in hatchery chinook catch in 2001 was

  13. Granitoid magmatism of Alarmaut granite-metamorphic dome, West Chukotka, NE Russia

    Science.gov (United States)

    Luchitskaya, M. V.; Sokolov, S. D.; Bondarenko, G. E.; Katkov, S. M.

    2009-04-01

    Main tectonic elements of West Chukotka are Alazey-Oloy, South-Anyui and Anyui-Chukotka fold systems, formed as a result of collision between structures of North-Asian continent active margin and Chukotka microcontinent [1-3]. South-Anyui fold system, separating Alazey-Oloy and Anyui-Chukotka systems, is considered as suture zon, formed as a result of oceanic basin closing [4-6]. Continent-microcontinent collision resulted in formation of large orogen with of northern and southern vergent structures, complicated by strike-slip deformations [7, 8]. Within Anyui-Chukotka fold system several rises, where most ancient deposits (crystalline basement and Paleozoic cover of Chukotka microcontinent) are exposed, were distinguished [2, 9-11]. Later they were considered as granite-metamorphic domes [12-14]. Alarmaut dome is located at West Chukotka to the north from Bilibino city and is traced from south to north in more than 120 km. General direction of structure is discordant to prevailing NW extensions of tectonic elements of the region. Paleozoic-Triassic deposits are exposed within the Alarmaut dome: 1) D3-C1 - crystalline schists, quartz-feldspar metasandstones, quartzites, marbles (700 m) [11]; 2) C1 - marblized limestones, quartz-feldspar metasandstones, quartzites, amphibole-pyroxene crystalline schists. Limestones contain corals, indicating Visean age of deposits [11]. Metamorphism reaches amphibolite facies, maximum P-T conditions are 660°С and 5 kbar. Migmatites, indicating in situ partial melting, are observed. Intensity of deformations of Paleozoic rocks increases at the boundary with Triassic deposits [11]; in the western part of dome slices of Pz rocks are separated by blastomylonite horizons [14]. Within Alramaut dome granitoids of Lupveem batholith (central part of dome), Bystrinsky pluton (southeastern part), and small Koyvel' and Kelil'vun plutons were studied. New U-Pb SHRIMP zircon data indicate Early Cretaceous (117-112 m.a.) age of granitoids [15

  14. Alteration and arenization processes of granitic waste rock piles from former uranium Mines in Limousin, France.

    Science.gov (United States)

    Kanzari, Aisha; Boekhout, Flora; Gérard, Martine; Galoisy, Laurence; Phrommavanh, Vannapha; Descostes, Michael

    2014-05-01

    France counts approximately 200 former uranium mines, 50 of which are located in the Limousin region. Mining activities between 1945 and 2001 have generated close to 200 000 tons of waste rocks in the Limousin, with uranium levels corresponding essentially to the geological background. Waste rock piles from three former mining sites in this region, were selected according to their age, uranium content and petrological signature. These sites are part of the two-mica granitic complex of St Sylvestre massif, formed 324 million years ago. Granitic blocks that build up the waste rock piles have experienced different processes and intensities of alteration before their emplacement at the surface. These processes are responsible for the petrological heterogeneity throughout the waste rock pile at the time of construction. It is important to make a distinction within waste rocks between natural-cut-off waste rocks and economic-cut-off waste rocks. The latter represents a minority and is linked to stock prices. Natural-cut-off waste rocks contain about 20 ppm of uranium; economic-cut-off waste rocks contain about 100 to 300 ppm of uranium. The aims of this study are to 1) assess the neo-formation of U-bearing minerals hosted by these rocks, and 2) to characterize the weathering processes since the construction of the rock piles, including both mechanical and chemical processes. The structure of the waste rocks piles, from metric blocks to boulders of tens centimeters, induces an enhanced weathering rate, compared to a granitic massif. Mechanical fracturing and chemical leaching by rainwater (arenization) of the waste rocks produce a sandy-silty alteration phase. Silty-clay weathering aureoles of submetric-granitic blocks evolving into technic soil are mainly located below growing birch trees. Sampling on the rock piles was restricted to surface rocks. Samples collected consist mainly of granites, and rare lamprophyres with a high radiometric signal, thereby especially

  15. Coastal biodiversity and bioresources: variation and sustainability

    Science.gov (United States)

    Qin, Song; Liu, Zhengyi; Yu, Roger Ziye

    2016-03-01

    The 1st International Coastal Biology Congress (1st ICBC) was held in Yantai, China, in Sep. 26-30, 2014. Eighteen manuscripts of the meeting presentations were selected in this special issue. According to the four themes set in the ICBC meeting, this special issue include four sections, i.e., Coastal Biodiversity under Global Change, Adaptation and Evolution to Special Environment of Coastal Zone, Sustainable Utilization of Coastal Bioresources, and Coastal Biotechnology. Recent advances in these filed are presented.

  16. Uranium in granites from the Southwestern United States: actinide parent-daughter systems, sites and mobilization. First year report

    Energy Technology Data Exchange (ETDEWEB)

    Silver, L T; Williams, I S; Woodhead, J A

    1980-10-01

    Some of the principal findings of the study on the Lawler Peak Granite are: the granite is dated precisely by this work at 1411 +- 3 m.y., confirming its synchroneity with a great regional terrane of granites. Uranium is presently 8-10 times crustal abundance and thorium 2-3 times in this granite. Uranium is found to be enriched in at least eight, possibly ten, primary igneous mineral species over the whole-rock values. Individual mineral species show distinct levels in, and characteristics ranges of, uranium concentration. It appears that in a uraniferous granite such as this, conventional accuracy mineral suites probably cannot account for most of the uranium in the rock, and more rare, high U-concentration phases also are present and are significant uranium hosts. It appears that at least two different geological episodes have contributed to the disturbance of the U-Th-Pb isotope systems. Studies of various sites for transient dispersal of uranium, thorium, and radiogenic lead isotopes indicate a non-uniform dispersal of these components. It appears that the bulk rock has lost at least 24 percent of its original uranium endowment, accepting limited or no radiogenic lead or thorium migration from the sample.

  17. Study on Kalimantan uranium province: The assessment on uranium mineralization of metamorphic and granitic rocks at Schwaner mountains

    International Nuclear Information System (INIS)

    Tjokrokardono, Soeprapto

    2002-01-01

    Uranium exploration activities done by CEA-BATAN had discovered uranium occurrences as the radiometric and uranium content anomalies at metamorphic and granite rocks of Schwaner Mountains, Kalimantan. A part of the occurrences on metamorphic rocks at Kalan basin has been evaluated and be developed onto follow-up step of prospecting by construction of some drilling holes and an exploration adit. In order to increase the national uranium resources, it is necessarily to extent the exploration activity to out side or nearby of Kalan basin. The goal of this assessment is to understand the uranium accumulation mechanism at Pinoh metamorphic rocks of Kalan Kalimantan and to delineate areas that uranium may exist. The assessment was based on the aspect of geology, anomaly of radioactivity and uranium contents, tectonics and alterations. Pinoh metamorphic rocks which is influenced by Sukadana granite intrusion are the high potential rocks for the uranium accumulation, because the intrusion contains a relatively high of U, Th, Cu, Zn, Nb, Mn, and W. The potential rock distributions are in between G. Ransa granite intrusion at the east and Kotabaru granite intrusions at the west. The mineralizations are categorized as vein type deposits of granitic association

  18. Uranium in granites from the Southwestern United States: actinide parent-daughter systems, sites and mobilization. First year report

    International Nuclear Information System (INIS)

    Silver, L.T.; Williams, I.S.; Woodhead, J.A.

    1980-10-01

    Some of the principal findings of the study on the Lawler Peak Granite are: the granite is dated precisely by this work at 1411 +- 3 m.y., confirming its synchroneity with a great regional terrane of granites. Uranium is presently 8-10 times crustal abundance and thorium 2-3 times in this granite. Uranium is found to be enriched in at least eight, possibly ten, primary igneous mineral species over the whole-rock values. Individual mineral species show distinct levels in, and characteristics ranges of, uranium concentration. It appears that in a uraniferous granite such as this, conventional accuracy mineral suites probably cannot account for most of the uranium in the rock, and more rare, high U-concentration phases also are present and are significant uranium hosts. It appears that at least two different geological episodes have contributed to the disturbance of the U-Th-Pb isotope systems. Studies of various sites for transient dispersal of uranium, thorium, and radiogenic lead isotopes indicate a non-uniform dispersal of these components. It appears that the bulk rock has lost at least 24 percent of its original uranium endowment, accepting limited or no radiogenic lead or thorium migration from the sample

  19. Preliminary study on influences of radioactivity of residential granite building materials upon parent mice and their offspring

    International Nuclear Information System (INIS)

    Liang Minyi; Zhang Jinghong; Zhu Weiyun; Li Yinyan; Liang Yongqing; Zhang Songshuan; Zhu Daming; Li Jinlin; Lu Qingpu

    2006-01-01

    Objective: To observe the effects of radioactivity of the residential granite building materials on the survival and fertility of mice. Methods: The radioactivities of A, B, C, and D granite building materials were measured and screened by gamma-ray spectrometer, and then these materials were placed into the mice cages. The residential radon was measured with solid state nuclear track detector's and 24-hour continuous measurement. Ninety-six healthy and ablactated mice were randomly selected and put into the four animal cages with different levels of radioactivity, and fed for 120 days. Mice mated and bred naturally. The fertilities and survivals of P, F 1 , and F 2 generation were observed and analyzed. Results: External exposures in the four mice cages were higher than those from the internal exposure. The differences of rates of pregnancy, abortion, and infertility between the P and F 1 generations had no statistical significance among all the groups after being fed for 120 days (P>0.05). There was significant difference among each group in the fertility of F 1 generation (P< 0.001), and the survival rates of the offspring were decreased with increase of radioactivity in granite building materials (P<0.001). Conclusion: Compared with the residential radon, the gamma rays released from the granite building materials had a greater influence on animals. The study suggested that different granite building materials had different influences on the survival and fertility of mice. (authors)

  20. Experimental and theoretical study of the Nd:YAG laser removal of beeswax on Galician granite at 355 nm

    Science.gov (United States)

    Pan, Aldara; Rebollar, Esther; Conde, J. Carlos; Lusquiños, Fernando; Chiussi, Stefano; León, Betty

    2010-09-01

    Beeswax coatings applied to seal off the granitic surfaces of many monuments have resulted in detrimental effects with time passing. Conservation procedures must be carried out in a selective way, removing the beeswax without any degradation of the stone. In this study we present an experimental analysis of the removal of beeswax using a Nd:YAG laser at a wavelength of 355 nm which is absorbed weakly by the beeswax. For this reason, an important percentage of the laser radiation reaches the granite substrate and the influence of the layer thickness must be studied. At each laser fluence, for single-pulse irradiation we find a maximum thickness for complete removal of the film. For thicker layers, the beeswax is not removed and additional effects such as color changes and thickness increase are observed. The experimental results suggest that a photomechanical mechanism is dominant and that granite absorption plays a fundamental role. Multiple-pulse irradiation is also performed to determine the optimal parameters for laser cleaning. Finally, infrared thermography measurements allow for the determination of the granite surface temperature after laser irradiation and theoretical calculations allow one to estimate the absorption behavior of granite at 355 and to explain the results obtained.

  1. Comparative evaluation of UV-vis-IR Nd:YAG laser cleaning of beeswax layers on granite substrates

    Energy Technology Data Exchange (ETDEWEB)

    Pan, A., E-mail: aldarapan@uvigo.es [Departamento de Fisica Aplicada, E.T.S.I Industriales, Universidad de Vigo, Rua Maxwell s/n. Campus Universitario Lagoas-Marcosende, E-36310 Vigo (Spain); Chiussi, S.; Gonzalez, P.; Serra, J.; Leon, B. [Departamento de Fisica Aplicada, E.T.S.I Industriales, Universidad de Vigo, Rua Maxwell s/n. Campus Universitario Lagoas-Marcosende, E-36310 Vigo (Spain)

    2011-04-15

    The beeswax treatment applied in the sixties to prevent rain water from penetrating the outer stone surface of valuable granitic Galician monuments is contributing to the acceleration of the superficial degradation process of these monuments. At present, the northern sector of the renaissance frieze in the Cloister of the Cathedral of Santiago de Compostela is one of the most representative examples. Conventional wax removal methods (water, chemical and mechanical cleaning) can possibly destruct important details of the relief. Therefore laser removal is considered as a good alternative. In this work, we report systematic investigations of the effect of laser cleaning at different Nd:YAG laser wavelengths (266, 355, 532 and 1064 nm) on representative samples of the real historical surfaces. Laser removal of beeswax on granite at neither of the four wavelengths of the Nd:YAG laser is not a layer by layer removal process. For each irradiance and wavelength there is a maximum thickness that can be completely removed by a single pulse. Above this thickness the waxy material is not removed, although it undergoes thermal modifications; since the fraction of radiation that reaches the granite substrate is not enough to trigger the ejection of material. Our results show that the wax-granite interface plays a fundamental role in granite cleaning, and when the wax is weakened by absorption of radiation at 266 nm, the removal process becomes more efficient.

  2. Pacific Coastal Salmon Recovery Fund

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Congress established the Pacific Coastal Salmon Recovery Fund (PCSRF) to monitor the restoration and conservation of Pacific salmon and steelhead populations and...

  3. Coastal Structures and Barriers 2012

    Data.gov (United States)

    California Department of Resources — This dataset is a compilation of the UCSC Sand Retention Structures, MC Barriers, and USACE Coastal Structures. UCSC Sand Retention Structures originate from a...

  4. NOAA Coastal Mapping Shoreline Products

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NOAA Coastal Mapping Shoreline Products from the Remote Sensing Division are primarily for application to the nautical charts produced by NOAA's Office of Coast...

  5. Coastal Structures and Barriers 2012

    Data.gov (United States)

    California Natural Resource Agency — This dataset is a compilation of the UCSC Sand Retention Structures, MC Barriers, and USACE Coastal Structures. UCSC Sand Retention Structures originate from a...

  6. STEER Coastal Use Mapping Project

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Coastal Use Mapping Project is designed to collect critical information on human activities in and near the St. Thomas East End Reserves (STEER). The project...

  7. Mineralogy and Geochemistry of Granitic rocks within Lichen Hills, Outback Nunatak, Northern Victoria Land, Antarctica

    Science.gov (United States)

    KIM, T.; KIM, Y.; Lee, I.; Lee, J.; Woo, J.

    2015-12-01

    The study areas, Lichen Hills and Outback Nunatak are located in the Northern Victoria Land which is close to Pacific Ocean side of Transantarctic Mountain (TAM), Antarctica. According to the study of Zeller and Dreschoff (1990), the radioactivity values of Lichen hills and Frontier Mt. area in the Victoria Land were very high. To identify the geochemical characteristics of granitic rocks in these areas, 13 samples of Lichen Hills rocks and 4 samples of Outback Nunatak rocks are analyzed. For mineralogical study, samples were observed in macroscale as well as microscale including microscope electron probe analysis. Rock samples of Lichen Hills, Outback Nunatak are mainly leucogranite and granitic pegmatite. These rock samples are composed of quartz, k-feldspar, plagioclase, muscovite, garnet, tourmaline like granite. In SEM-EDS analysis, the observed light colored minerals show relatively high Th, U, Dy, Ce, Nb concentration. This suggests that rock samples may contain minerals such as fergusonite, monazite, thorite, allanite, karnasurtite which are considered to be REE-bearing minerals. Samples of related rocks have been analyzed in terms of major, trace and rare earth element (REE) concentrations using X-ray fluorescence (XRF) spectrometer and Inductively Coupled Plasma Mass Spectrometer (ICP-MS). As concentration of SiO2 increase, Al2O3, TiO2, Fe2O3, MgO, P2O5 concentration decrease and Na2O, K2O, MnO concentration increase. Analyzed trace elements and REE are normalized using CI Chondrite, Primitive mantle. The normalized data show that LREE are enriched compared to HREE. The distinct negative anomalies of Eu, Sr are observed, indicating that rock-forming melts are fairly processed state of fractional crystallization. It means that Th, U, Nb, Ta are much enriched in the melts.

  8. Responses of Chironomidae (Diptera; Insecta to the exclusion of shrimps and Ephemeroptera in a coastal forest stream, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    ML. Souza

    Full Text Available In a benthic community on a continuous flat granite substrate in a third-order coastal forest stream, the dominant chironomid (Cricotopus increased in number when shrimps (Macrobrachium olfersi and Potimirim glabra and baetid ephemeropterans were excluded by electricity. The response appeared to be mediated by an increase in periphyton and sediments, rather than a reduction of direct predation or interference. Chironomids, periphyton and sediments decreased significantly compared to the control when shrimps only were excluded. Baetid ephemeropteran appeared to be the most important determinants of periphyton and sediment mass; the density of chironomids appeared to follow the quantity of periphyton and sediments.

  9. Ecologically Enhancing Coastal Infrastructure

    Science.gov (United States)

    Mac Arthur, Mairi; Naylor, Larissa; Hansom, Jim; Burrows, Mike; Boyd, Ian

    2017-04-01

    Hard engineering structures continue to proliferate in the coastal zone globally in response to increasing pressures associated with rising sea levels, coastal flooding and erosion. These structures are typically plain-cast by design and function as poor ecological surrogates for natural rocky shores which are highly topographically complex and host a range of available microhabitats for intertidal species. Ecological enhancement mitigates some of these negative impacts by integrating components of nature into the construction and design of these structures to improve their sustainability, resilience and multifunctionality. In the largest UK ecological enhancement trial to date, 184 tiles (15x15cm) of up to nine potential designs were deployed on vertical concrete coastal infrastructure in 2016 at three sites across the UK (Saltcoats, Blackness and Isle of Wight). The surface texture and complexity of the tiles were varied to test the effect of settlement surface texture at the mm-cm scale of enhancement on the success of colonisation and biodiversity in the mid-upper intertidal zone in order to answer the following experimental hypotheses: • Tiles with mm-scale geomorphic complexity will have greater barnacle abundances • Tiles with cm-scale geomorphic complexity will have greater species richness than mm-scale tiles. A range of methods were used in creating the tile designs including terrestrial laser scanning of creviced rock surfaces to mimic natural rocky shore complexity as well as artificially generated complexity using computer software. The designs replicated the topographic features of high ecological importance found on natural rocky shores and promoted species recruitment and community composition on artificial surfaces; thus enabling us to evaluate biological responses to geomorphic complexity in a controlled field trial. At two of the sites, the roughest tile designs (cm scale) did not have the highest levels of barnacle recruits which were

  10. Ocean and coastal data management

    Science.gov (United States)

    de La Beaujardière, Jeff; Beegle-Krause, C; Bermudez, Luis; Hankin, Steven C.; Hazard, Lisa; Howlett, Eoin; Le, Steven; Proctor, Roger; Signell, Richard P.; Snowden, Derrick P.; Thomas, Julie

    2010-01-01

    We introduce data management concepts, including what we mean by "data" and its "management," sources of data, interoperability, and data geometry. We then discuss various components of a data management system. Finally, we summarize some existing ocean and coastal data management efforts. We make specific recommendations throughout the paper. We are generally optimistic that ocean and coastal data management is an interesting and solvable challenge that will provide great benefit to society.

  11. Petrogenesis of peralkaline granite dykes of the Straumsvola complex, western Dronning Maud Land, Antarctica

    Science.gov (United States)

    Harris, Chris; Dreyer, Tanya; le Roux, Petrus

    2018-01-01

    Peralkaline syenite and granite dykes cut the Straumsvola nepheline syenite pluton in Western Dronning Maud Land, Antarctica. The average peralkalinity index (PI = molecular Al/[Na + K]) of the dykes is 1.20 ( n = 29) and manifests itself in the presence of the Zr silicates eudialyte, dalyite and vlasovite, and the Na-Ti silicate, narsarsukite. The dykes appear to have intruded during slow cooling of the nepheline syenite pluton, and the petrogenetic relationship of the dykes and the pluton cannot be related to closed-system processes at low pressure, given the thermal divide that exists between silica-undersaturated and oversaturated magmas. Major and trace element variations in the dykes are consistent with a combination of fractional crystallization of parental peralkaline magma of quartz trachyte composition, and internal mineral segregation prior to final solidification. The distribution of accessory minerals is consistent with late-stage crystallization of isolated melt pockets. The dykes give an Rb-Sr isochron age of 171 ± 4.4 Ma, with variable initial 87Sr/86Sr ratio (0.7075 ± 0.0032), and have an average ɛ Nd of - 12.0. Quartz phenocrysts have δ18O values of 8.4-9.2‰, which are generally in O-isotope equilibrium with bulk rock. Differences in the δ18O values of quartz and aegirine (average Δquartz-aegirine = 3.5‰) suggest aegirine formation temperatures around 500 °C, lower than expected for a felsic magma, but consistent with poikilitic aegirine that indicates subsolidus growth. The negative ɛ Nd (values averaging 8.6‰ (assuming Δquartz-magma = 0.6‰) are inconsistent with a magma produced by closed-system fractional crystallization of a mantle-derived magma. By contrast, the nepheline syenite magma had mantle-like δ18O values and much less negative ɛ Nd (average - 3.1, n = 3). The country rock has similar δ18O values to the granite dykes (average 8.0‰, n = 108); this means that models for the petrogenesis of the granites by

  12. Determination of low concentrations of uranium in granite samples by X-ray fluorescence

    International Nuclear Information System (INIS)

    Roca, M.; Diaz-Guerra, J.P.

    1981-01-01

    An x-ray fluorescence method for the determination of uranium in granite samples for concentrations ranging from 3 to 100 ppm U 3 O 8 has been developed. To this purpose a sample holder, specially designed, allowing the irradiation of sample surfaces 42.5 mm in diameter and a molybdenum tube operating with a power of 2700 W (90 kV, 30 mA) are used. The background influence and the spectral interferences from rubidium and strontium have been taken into account and specific correction coefficients have been computed. A Basic program facilitates the report of the analytical results. (author)

  13. Geologic map of the Granite 7.5' quadrangle, Lake and Chaffee Counties, Colorado

    Science.gov (United States)

    Shroba, Ralph R.; Kellogg, Karl S.; Brandt, Theodore R.

    2014-01-01

    The geologic map of the Granite 7.5' quadrangle, Lake and Chaffee Counties, Colorado, portrays the geology in the upper Arkansas valley and along the lower flanks of the Sawatch Range and Mosquito Range near the town of Granite. The oldest rocks, exposed in the southern and eastern parts of the quadrangle, include gneiss and plutonic rocks of Paleoproterozoic age. These rocks are intruded by younger plutonic rocks of Mesoproterozoic age. Felsic hypabyssal dikes, plugs, and plutons, ranging in age from Late Cretaceous or Paleocene to late Oligocene, locally intruded Proterozoic rocks. A small andesite lava flow of upper Oligocene age overlies Paleoproterozoic rock, just south of the Twin Lakes Reservoir. Gravelly fluvial and fan deposits of the Miocene and lower Pliocene(?) Dry Union Formation are preserved in the post-30 Ma upper Arkansas valley graben, a northern extension of the Rio Grande rift. Mostly north-northwest-trending faults displace deposits of the Dry Union Formation and older rock units. Light detection and ranging (lidar) imagery suggests that two short faults, near the Arkansas River, may displace surficial deposits as young as middle Pleistocene. Surficial deposits of middle Pleistocene to Holocene age are widespread in the Granite quadrangle, particularly in the major valleys and on slopes underlain by the Dry Union Formation. The main deposits are glacial outwash and post-glacial alluvium; mass-movement deposits transported by creep, debris flow, landsliding, and rockfall; till deposited during the Pinedale, Bull Lake, and pre-Bull Lake glaciations; rock-glacier deposits; and placer-tailings deposits formed by hydraulic mining and other mining methods used to concentrate native gold. Hydrologic and geologic processes locally affect use of the land and locally may be of concern regarding the stability of buildings and infrastructure, chiefly in low-lying areas along and near stream channels and locally in areas of moderate to steep slopes. Low

  14. Temporal evolution of a granitic rock under thermal loads generated by fission products

    International Nuclear Information System (INIS)

    Ventura, M.A.; Ferreri, J.C.

    1985-01-01

    A parametric study of the thermal history of a granitic mass under thermal loads originating in terminal subproducts of the fuel cycle is performed. Variations of the conductivity and density of the rock and the unit cell dimensions are considered. In this way it was tried to delimit (for short time intervals of the order of 100 years) the influence of possible uncertainties in the rock's knowledge on the results of interest for the engineering design. In the reasonable situations considered, the maximum temperature in the rock did not rise over 80 deg C. (Author) [es

  15. Laboratory experiments for understanding mechanical properties of fractured granite under supercritical conditions

    Science.gov (United States)

    Kitamura, M.; Takahashi, M.; Takagi, K.; Hirano, N.; Tsuchiya, N.

    2017-12-01

    To extract geothermal energy effectively and safely from magma and/or adjacent hot rock, we need to tackle many issues which require new technology development, such as a technique to control a risk from induced-earthquakes. On a development of induced-earthquake mitigation technology, it is required to understand roles of factors on occurrences of the induced-earthquake (e.g., strength, crack density, and fluid-rock reaction) and their intercorrelations (e.g., Asanuma et al., 2012). Our purpose of this series of experiments is to clarify a relationship between the rock strength and the crack density under supercritical conditions. We conducted triaxial deformation test on intact granite rock strength under high-temperature (250 - 750°C), high-pressure (104 MPa) condition at a constant load velocity (0.1 μm/sec) using a gas-rig at AIST. We used Oshima granite, which has initially stress drop became smaller at higher temperature. Young's modulus increased with decreasing the temperature from 32.3 GPa at 750°C to 57.4 GPa at 250°C. At 400 °C, the stress drop accelerated the deformation with 98 times faster velocity than that at load-point. In contrast, at 650°C and 750°C, the velocity during stress drop kept the same order of the load-point velocity. Therefore, the deformation mechanism may start to be changed from brittle to ductile when the temperature exceeds 650°C. Highly dense cracked granite specimens were formed by a rapid decompression test (RDT) using an autoclave settled at Tohoku University (Hirano et al., 2016JpGU), caused by a reduction of fluid pressure within 1-2 sec from vapor/supercritical state (10 - 48 MPa, 550 °C) to ambient pressure. The specimens after RDT show numerous microcracks on X-ray CT images. The RDT imposed the porosity increasing towards 3.75 % and Vp and Vs decreasing towards 1.37±0.52 km/s and 0.97±0.25 km/s. The Poisson's ratio shows the negative values in dry and 0.5 in wet. In the meeting, we will present results of

  16. Rb-Sr age estimation of granites-gneisses of Belopotokskij type (Soviet Carpathians)

    International Nuclear Information System (INIS)

    Stepanyuk, L.M.; Kotlovskaya, F.I.; Dovbush, T.I.

    1987-01-01

    Using rubidium-strontium method the age of granito-gneisses of Belopotokskij type of 470 ± 6 mln. years, which agree with isotopic age (459 ± 6 mln. years) obtained by uranium-lead isochronous method using syngenetic zircon, is established. The latter testifies to the manifestation of magmatic activity 460-470 mln. years ago. The low initial ratio of strontium isotopes 87 Sr/ 86 Sr and results of petrographic study of fel spars are indicative of magmatic nature of initial granites and plutonic (mantle or lower crust) source of magma, crystallization of which was the beginning of the Belopotokskij type granito-gneiss formation

  17. Thermal cracking in Lac du Bonnet granite during slow heating to 205 degrees celsius

    International Nuclear Information System (INIS)

    Chernis, P.J.; Robertson, P.B.

    1993-09-01

    Acoustic emissions (AE) were recorded as drill core samples of Lac du Bonnet granite were slowly heated to between 66 and 205 degrees celsius to evaluate the effects of temperature on the properties of rock samples. Longitudinal and shear velocities of the samples were measured, and Young's moduli, shear moduli and Poisson's ratios were calculated. No significant AE activity was detected until temperatures reached approximately 73-80 degrees celsius. Above this 'threshold' temperature, calculated rock properties decreased, and at 205 degrees celsius calculated Young's modulus, shear modulus, and Poisson's ratio were reduced by 30, 26, and 29% respectively

  18. Studies on geneses of Lianshanguan granites and Lianshanguan uranium ore deposit

    International Nuclear Information System (INIS)

    Zhang Jiafu; Xu Guoqing; Wang Wenguang

    1994-02-01

    Based on the field work, and through the studies of thin-sections, minerals fluid inclusions, isotope geology, rare-earth elements and U-content in rocks and minerals, it is suggested that Lianshanguan granites are of magmatization genesis with multistage. The genetic model of mineralization of Lianshanguan uranium ore deposit is the magmatization-hydrothermal-filled uranium type. The role of mineralization of uranium ore deposit in that area is discussed. Furthermore, the direction of prospecting and following prospecting criteria for similar deposits in this area are also given

  19. Oxigen isotope compositions as indicators of epidote granite genesis in the Borborema Provinces, NE Brazil

    International Nuclear Information System (INIS)

    Ferreira, V.P.; Valley, J.W; Sial, A.N; Spicuzza, M.J

    2001-01-01

    Neoproterozoic magmatic epidote-bearing granitoids intrude low-grade metapelites in the Cachoeirinha-Salgueiro terrane (CST), and gneisses and migmatites in the Serido terrane (ST), in the Borborema structural province, northeastern Brazil. Granitoids in both terranes contain biotite and hornblende, and are metaluminous, calc-alkalic, and oxidized I-type granites according to White's (1992) classification. However, in spite of these similarities, this work shows that mineral oxygen isotope data from plutons of the two terranes indicate different magma sources, and that magmatic epidote besides crystallizing at different pressure conditions, can have variable isotopic composition (au)

  20. Vertical evolution of the Cínovec granite cupola – chemical and mineralogical record

    Czech Academy of Sciences Publication Activity Database

    Breiter, Karel

    2016-01-01

    Roč. 46 (2016), s. 4-6 E-ISSN 1434-7512. [Late Paleozoic magmatism in the Erzgebirge / Krušné hory: Magma genesis, tectonics, geophysics, and mineral deposits : abstracts. 11.11.2016-12.11.2016, Freiberg] R&D Projects: GA ČR GA14-13600S Institutional support: RVO:67985831 Keywords : granite * Cínovec * geology * mineralogy * geochemistry Subject RIV: DB - Geology ; Mineralogy http://tu-freiberg.de/sites/default/files/media/institut-fuer-geologie-718/pdf/fog_volume_46.pdf

  1. Influence de la structure des gneiss et des granites sur la resistance ...

    African Journals Online (AJOL)

    A partir de la structure des roches (gneiss et granites) provenant des différentes régions du Togo il a été proposée une classification basée sur le modèle exponentielle appliquée à la probabilité de présence de grains de dimensions variables. Cette classification a permis d'évaluer l'homogénéité granulaire des roches de ...

  2. Fracture hydrology relevant to radionuclide transport. Field work in a granite formation in Cornwall

    International Nuclear Information System (INIS)

    Bourke, P.J.; Hodgkinson, D.P.; Durrance, E.M.; Heath, M.J.

    1985-01-01

    Separation, orientation, apertures and intersections of water-bearing fractures are the variables which control water flow and affect radionuclide transport through fractured rocks. The need is discussed for information on the distribution of these variables in statistical treatments of flow and transport, because of the inadequacy of permeability and porosity data in continuum treatments. Satisfactory methods of measuring distributions of separation, orientation and apetures have been developed and data for Cornish granite are presented. An estimate of the average distance between fracture intersections is made

  3. Study of heat diffusion in a granitic geologic formation of high level radioactive wastes

    International Nuclear Information System (INIS)

    Goldstein, S.; Juignet, N.

    1980-06-01

    Thermal study of granitic underground storage of vitrified high level radioactive wastes in a regular network of shafts and galleries. The aim is to show influence on temperature rise of the geologic formation of main parameters to define the storage zone and to determine the network dimension in function of the rock properties. Two models were studied allowing a rapid variation of geometrical and physical parameters. A numerical method using finite element method or Green functions were used for calculations. Temperatures are determined either for the whole storage site or a unit cell of the lattice [fr

  4. Mechanical and thermomechanical calculations related to the storage of spent nuclear-fuel assemblies in granite

    International Nuclear Information System (INIS)

    Butkovich, T.R.

    1980-05-01

    A generic test of the geologic storage of spent-fuel assemblies is being made at Nevada Test Site. The spent-fuel assemblies were emplaced at a depth of 420 m (1370 ft) below the surface in a typical granite and will be retrieved at a later time. The early time, close-in thermal history of this type of repository is being simulated with spent-fuel and electrically heated canisters in a central drift, with auxiliary heaters in two parallel side drifts. Prior to emplacement of the spent-fuel canisters, preliminary calculations were made using a pair of existing finite-element codes, ADINA and ADINAT

  5. The 131-134 Ma A-type granites from northern Zhejiang Province, South China: Implications for partial melting of the Neoproterozoic lower crust

    Science.gov (United States)

    Hu, Qinghai; Yu, Kaizhang; Liu, Yongsheng; Hu, Zhaochu; Zong, Keqing

    2017-12-01

    Although Mesozoic granites are widely distributed in the Gan-Hang Belt in Southeast China, their petrogenesis and geodynamic settings are still matters of dispute. Here, the major and trace elements, Sr-Nd isotopic compositions, zircon U-Pb dating and Hf isotopes of three late Mesozoic granite plutons from Machebu, Shenzhongwu and Daixi in northern Zhejiang Province were analyzed to investigate their petrogenesis. These granite plutons are featured by an A2-type granite geochemical signature (e.g., high SiO2 (71 to 78 wt.%), total alkalis (Na2O + K2O = 7.57 to 9.12 wt.%), rare earth elements (total REE = 174 to 519 ppm) and HFSE contents, with mostly high FeOT/(FeOT + MgO) (0.82 to 0.93) and Ga/Al ratios (2.49 to 5.07) and low Ce4 +/Ce3 + ratios in zircons (1 to 90)), suggesting they were formed in an extensional tectonic setting. Combining whole rock Zr contents, mineral assemblages and the An content of plagioclase, it was suggested that these granites could have formed at a high temperature (> 850 °C) with a low H2O content ( 2.5 wt.%). Assuming the granite with the lowest SiO2 and high CaO contents as the "primary granite melt", the melting pressure was estimated to be 2.5 kbar based on model calculations using MELTs. Taking into account the effect of plagioclase fractional crystallization during the granite emplacement into shallow crustal levels, the initial melting pressure could be > 2.5 kbar at the stable field of plagioclase. This agrees well with the very low and variable Sr and Eu contents of these granite plutons. Zircon U-Pb dating yields a weighted mean 206Pb/238U age of 130.9 ± 1.0 Ma for the Machebu granite, 134.4 ± 2.1 Ma for the Shenzhongwu granite and 131.9 ± 1.2 Ma for the Daixi granite. The εHf(t) values of the zircons in these plutons gradually increase from southwest to northeast, i.e., from - 14.5 - 3.5 for the Machebu granite to - 1.5 - 0.2 for the Shenzhongwu granite and from 5.1 8.6 for the Daixi granite, suggesting the origin of

  6. Coastal Research Imaging Spectrometer

    Science.gov (United States)

    Lucey, Paul G.; Williams, Timothy; Horton, Keith A.

    2004-01-01

    The Coastal Research Imaging Spectrometer (CRIS) is an airborne remote sensing system designed specifically for research on the physical, chemical, and biological characteristics of coastal waters. The CRIS includes a visible-light hyperspectral imaging subsystem for measuring the color of water, which contains information on the biota, sediment, and nutrient contents of the water. The CRIS also includes an infrared imaging subsystem, which provides information on the temperature of the water. The combination of measurements enables investigation of biological effects of both natural and artificial flows of water from land into the ocean, including diffuse and point-source flows that may contain biological and/or chemical pollutants. Temperature is an important element of such measurements because temperature contrasts can often be used to distinguish among flows from different sources: for example, a sewage outflow could manifest itself in spectral images as a local high-temperature anomaly. Both the visible and infrared subsystems scan in pushbroom mode: that is, an aircraft carrying the system moves along a ground track, the system is aimed downward, and image data are acquired in across-track linear arrays of pixels. Both subsystems operate at a frame rate of 30 Hz. The infrared and visible-light optics are adjusted so that both subsystems are aimed at the same moving swath, which has across-track angular width of 15 . Data from the infrared and visible imaging subsystems are stored in the same file along with aircraft- position data acquired by a Global Positioning System receiver. The combination of the three sets of data is used to construct infrared and hyperspectral maps of scanned areas (see figure). The visible subsystem is based on a grating spectrograph and a rapid-readout charge-coupled-device camera. Images of the swatch are acquired in 256 spectral bands at wavelengths from 400 to 800 nm. The infrared subsystem, which is sensitive in a single

  7. Geochronology and geochemistry of the granites from the Zhuxi W-Cu ore deposit in South China: Implication for petrogenesis, geodynamical setting and mineralization

    Science.gov (United States)

    Pan, Xiaofei; Hou, Zengqian; Zhao, Miao; Chen, Guohua; Rao, Jianfeng; Li, Yan; Wei, Jin; Ouyang, Yongpeng

    2018-04-01

    The giant Zhuxi tungsten deposit is located in the Taqian-Fuchun Ore Belt in northeastern Jiangxi province, and genetically associated with the Zhuxi granitic stocks and dykes. Three mineralization-related granites including granite porphyry dykes (GP), biotite granitic stocks (BG), and white granitic dykes (WG), were identified in the Zhuxi deposit. SHRIMP zircon U-Pb analysis for the three granitic rocks present ages ranging from 153.5 ± 1.0 Ma to 150.4 ± 1.0 Ma. The BG mainly contains quartz, microcline, albite, biotite and muscovite with minor accessory minerals including zircon, apatite, monazite, Ti/Fe oxides, and dolerite. However, the WG is mainly composed of quartz, microcline and albite with minor muscovite and accessory minerals. The GP is a medium-grained porphyritic granite and its phenocrysts include quartz, alkali feldspar, muscovite and plagioclase. All the Zhuxi granites have high SiO2 content (71.97 wt%-81.19 wt%) and total alkali (3.25 wt%-9.42 wt%), and their valid aluminum saturation index (ASI) values show a wide range of 1.03 to 2.49. High Rb/Sr ratios, low Sr content (values fall into the ranges of -6.98 to -11.97, and -3.1 to -11.5, and the Nd (TDM2) and Hf two-stage model ages (TDMc) are 1.51-1.92 Ga and 1.42-2.01 Ga, respectively. Geochemical and isotopic data suggest that these highly fractionated I-S transform-type granites were originated from magmas which showed affinity with the Proterozoic continent and the Shuangqiaoshan Group and little mantle contribution was involved during the generation of Zhuxi granitic rocks. Extreme fractional crystallization resulted in further enrichment of tungsten in the evolved granitic magma. New data, presented together with previously published data, suggest that the Zhuxi granitic complex was likely to be formed during lithospheric compression setting during the late Jurassic to early Cretaceous. The biotite granite stock predominately contributed to the production of skarn alteration and

  8. Study of the incorporation of marble and granite wastes in the raw material to produce glass wool

    International Nuclear Information System (INIS)

    Rodrigues, Girley Ferreira; Junca, Eduardo; Telles, Victor Bridi; Espinosa, Denise Crocce Romano; Tenorio, Jorge Alberto Soares; Alves, Joner Oliveira

    2010-01-01

    The study aimed to characterize materials obtained from the melted mixture containing marble and granite wastes, and also chemical reagents. Using the characterization results was defined the feasibility of reuse of the marble and granite wastes, through the incorporation in the raw material to produce glass wool (a material with great consumer market as thermo-acoustic insulator). The batch was poured in a water-filled recipient and also in a Herty viscometer at temperatures of 1400, 1450 and 1500 °C. Samples of produced materials were characterized by morphology using Scanning Electron Microscopy, by atomic structure using X-ray Diffraction, and by thermal behavior using Differential Thermal Analysis. The total amount of marble and granite wastes can reach about 79% replacement in relation to the total weight of the raw material used in the glass wool production. (author)

  9. The granitic complex of Brame/Saint-Sylvestre/Saint-Goussaud (French Massif Central), geochemical mapping applied to uranium prospecting

    International Nuclear Information System (INIS)

    Valois, J.P.

    1991-01-01

    Obtained geochemic data from the granitic complex of Brame/Saint-Sylvestre/Saint-Goussaud (French Massif Central), which is known as uranium ore bearing. Friedrich's data were reinterpreted using a different statistical method (principal component analysis with oblic rotation of the factors). The resulting trace element associations are interpreted according to the several mineral paragenesis previously described in this complex. These associations can be related to the successive stages of granitic cristallisation, and their mapping is in agreement with previous mapping obtained from quite different data (structural petrology for example). New results concern an U, Zn, Y, R.E association which is attributed to the uraninite paragenesis, previously described on this granitic complex. Mapping this last association contributes to emphasize the central part of the complex as a favourable zone for prospecting [fr

  10. Granite landforms

    National Research Council Canada - National Science Library

    Twidale, C. R

    1982-01-01

    ... may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of...

  11. Crystal Cargo Characterization: Unravelling Granite Petrogenesis through Combined MicroXRF Imaging and In-situ Analyses.

    Science.gov (United States)

    McLeod, C. L.; Brown, K.; Brydon, R.; Haley, M.; Hill, T.; Shaulis, B.; Tronnes, R. G.

    2017-12-01

    Advances in the capabilities of microanalysis over the past several decades have promoted a redefinition of traditional petrological terminology. This has allowed a more accurate evaluation of a samples petrogenetic history. For example, the term "phenocryst", specifically describes crystals that grew from the liquid that solidified into the groundmass. Evolving from this idea is the term xenocryst, referring to crystals that did not originate in the magma but were gathered by it, and antecrysts, which crystallized from a progenitor of the magma that solidified into the groundmass. Through identification of a magmas different, and distinct, crystal populations, the petrogenetic history of a magmatic rock can therefore be unraveled. This approach has been widely applied to terrestrial volcanic systems throughout the past several decades. This study presents results from a combined microimaging and in-situ microanalytical investigation of granitic magmas crystal cargoes in order to unravel how granitic batholiths are constructed. 27 lithological units from two granite batholiths in the Oslo Rift, Norway form the basis of this investigation. Micro X-Ray Fluorescence (µXRF) mapping of major elements and selected trace elements is used in order to chemically map each granitic unit, identify any characteristic growth zoning, and compare the crystal cargoes of the different units. Major and trace elemental abundances of the major phases (feldspars, biotite, amphibole) and minor phases (apatite and titanite) are to be quantified through electron microprobe analysis (EPMA) and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) respectively. Through chemically fingerprinting the crystal cargoes of these Oslo Rift granitic magmas, the open vs. closed nature of granitic, intrusive, magmatic systems will be investigated. Within the context of the Oslo Rift, this study also offers an opportunity to evaluate the processes inherent to granitoid magmatism

  12. Smolt Condition and Timing of Arrival at Lower Granite Reservoir, 1985 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Scully, Richard J.; Buettner, Edwin W.

    1986-08-01

    This project monitored the daily passage of smolts during the 1985 spring outmigration at three migrant traps, one each on the Snake, Clearwater, and Salmon rivers. Yearling chinook migration rate between Salmon River release sites and the Salmon River scoop trap averaged 23 km per day, about half the migration rate for the same brand groups when migrating from the Salmon River trap to the Snake River trap (48 km/day). Average migration rates for branded chinook and steelhead between release sites and the head of Lower Granite Reservoir were both near 27 km per day. The yearling chinook migration begins in earnest when Salmon River discharge makes a significant rise in early to mid-April. Most yearling chinook pass into Lower Granite Reservoir in April followed by passage of steelhead in May. Chinook smolt recapture data from the Snake River trap suggest a strong dependence of migration rate on quantity of Snake and Salmon river discharge. The ability of the Salmon River trap to catch yearling chinook decreased as discharge increased. No correlation between discharge level and efficiency was observed at the Snake or Clearwater trap for chinook or steelhead smolts. When comparing the size of smolts in the Salmon and Clearwater rivers, the former river has smaller yearling chinook and larger hatchery and wild steelhead. Salmon River hatchery steelhead smolts in 1985 averaged 2 cm smaller than in 1983 and were much healthier than in 1983. 4 refs., 32 figs., 18 tabs.

  13. Smolt Condition and Timing of Arrival at Lower Granite Reservoir, 1986 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Nelson, V. Lance

    1987-09-01

    This project monitored the daily passage of smolts during the 1986 spring outmigration at two migrant traps, one each on the Snake and Clearwater rivers. Average migration rates for freeze-branded chinook salmon smolts were 28.2 km per day and 22.1 km per day for steelhead trout smolts between release sites and the head of Lower Granite Reservoir. The yearling chinook salmon migration begins in earnest when Salmon River discharge makes a significant rise in early to mid-April. Most yearling chinook salmon pass into Lower Granite Reservoir in April followed by passage of steelhead trout in May. Chinook salmon smolt recapture data from the Snake River trap suggest a strong dependence of migration rate on quantity of Snake and Salmon River discharge, although no statistical correlation exists at this time. Daily and seasonal descaling rates were calculated for each species at each trap. Rates were highest for hatchery steelhead trout, intermediate for yearling chinook salmon, and lowest for wild steelhead trout. Descaling rates were generally higher in 1986 than those observed in 1984 and 1985. 4 refs., 9 figs., 15 tabs.

  14. Smolt Condition and Timing of Arrival at Lower Granite Reservoir, 1987 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Nelson, V. Lance

    1990-01-01

    This project monitored the daily passage of smolts during the 1988 spring outmigration at two migrant traps; one each on the Snake and Clearwater rivers. Due to the low runoff year, chinook salmon catch at the Snake River trap was very low. Steelhead trout catch was higher than normal, probably due to trap modifications and because the trap was moved to the east side of the river. Chinook salmon and steelhead trout catch at the Clearwater River trap was similar to 1987. Total cumulative recovery of PIT tagged fish at the three dams, with PIT tag detection systems was: 55% for chinook salmon, 73% for hatchery steelhead trout, and 75% for wild steelhead trout. Travel time through Lower Granite Reservoir for PIT tagged chinook salmon and steelhead trout, marked at the head of the reservoir, was affected by discharge. Statistical analysis showed that as discharge increased from 40 kcfs to 80 kcfs, chinook salmon travel time decreased three fold, and steelhead trout travel time decreased two fold. There was a statistical difference between estimates of travel time through Lower Granite Reservoir for PIT tagged and freeze branded steelhead trout, but not for chinook salmon. These differences may be related to the estimation techniques used for PIT tagged and freeze branded groups, rather than real differences in travel time. 10 figs, 15 tabs.

  15. Smolt Condition and Timing of Arrival at Lower Granite Reservoir, 1988 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Nelson, William R.

    1989-10-01

    This project monitored the daily passage of smelts during the 1988 spring outmigration at two migrant traps; one each on the Snake and Clear-water rivers. Due to the low runoff year, chinook salmon catch at the Snake River trap was very low. Steelhead trout catch was higher than normal, probably due to trap modifications and because the trap was moved to the east side of the river. Chinook salmon and steelhead trout catch at the Clearwater River trap was similar to 1987. Total cumulative recovery of PIT tagged fish at the three dams, with PIT tag detection systems was: 55% for chinook salmon, 73% for hatchery steelhead trout, and 75% for wild steelhead trout. Travel time through Lower Granite Reservoir for PIT tagged chinook salmon and steelhead trout, marked at the head of the reservoir, was affected by discharge. Statistical analysis showed that as discharge increased from 40 kcfs to 80 kcfs, chinook salmon travel time decreased three fold, and steelhead trout travel time decreased two fold. There was a statistical difference between estimates of travel time through Lower Granite Reservoir for PIT tagged and freeze branded steelhead trout, but not for chinook salmon. These differences may be related to the estimation techniques used for PIT tagged and freeze branded groups, rather than real differences in travel time.

  16. Distribution of uranium and thorium in sediments and plants from a granitic fluvial area

    International Nuclear Information System (INIS)

    Vargas, M.J.; Tome, F.V.; Sanchez, A.M.; Vazquez, M.T.C.; Murillo, J.L.G.

    1997-01-01

    A study of the presence of natural uranium and thorium isotopes in sediments and plants belonging to a granitic fluvial region of the Ortigas river (west of Spain) has been carried out. The existence of two uranium mines in the neighbourhood of the sampled sites and the granitic characteristics of the zone produce significant concentrations of natural radionuclides. Temporal and spatial variations of uranium and thorium concentrations and the activity ratios 234 U/ 238 U, 228 Th/ 232 Th and Th/U were studied to better understand the mobilization mechanisms such as leaching and transport at play in the studied system. These determinations were made using alpha-particle spectrometry with silicon detectors. The measurements were also compared with the results previously found for waters of this fluvial area. Uranium in sediments showed variations due to changes in rainfall, but thorium content was nearly constant. Uranium and thorium concentrations in plants were lower after rainfall. Incorporation of uranium into the plants seemed to be mainly from water, whereas incorporation of thorium seemed to be from both sediments and water. (Author)

  17. Performance assessment of geological isolation systems for radioactive waste. Disposal in granite formations

    International Nuclear Information System (INIS)

    Van Kote, F.; Peres, J.M.; Olivier, M.; Lewi, J.; Assouline, M.; Mejon-Goula, M.J.

    1988-01-01

    In the framework of the PAGIS project of the CEC Research Programme on radioactive wastes, a performance assessment of a repository of vitrified HLW in granite was carried out. Three disposal sites were considered: the reference site Auriat and two alternative sites, Barfleur and a site in the U.K. The report describes the methodology adopted (a deterministic and a stochastic approach) with the corresponding data base and the models used. A parametric study of sub-systems (near field, far field and biosphere) was carried out by CEA-ANDRA using AQUARIUS, DIMITRIO and BIOS. A global evaluation of the performances was carried out by CEA-IPSN using MELODIE code. The results of deterministic calculations showed for Auriat a maximum dose equivalent evaluated at 6.10 -3 m Sv/a arising 3 millions years after disposal. Results of human intrusion scenario analyses, uncertainty analyses and global sensitivity analyses are presented. This document is one of a set of 5 reports covering a relevant project of the European Community on a nuclear safety subject having very wide interest. The five volumes are: the summary (EUR 11775-EN), the clay (EUR 11776-EN), the granite (EUR 11777-FR), the salt (EUR 11778-EN) and the sub-seabed (EUR 11779-EN)

  18. Assessment of the Alteration of Granitic Rocks and its Influence on Alkalis Release

    Science.gov (United States)

    Ferraz, Ana Rita; Fernandes, Isabel; Soares, Dora; Santos Silva, António; Quinta-Ferreira, Mário

    2017-12-01

    Several concrete structures had shown signs of degradation some years after construction due to internal expansive reactions. Among these reactions there are the alkali-aggregate reactions (AAR) that occur between the aggregates and the concrete interstitial fluids which can be divided in two types: the alkali-silica reaction (ASR) and alkali-carbonate reaction (ACR). The more common is the ASR which occurs when certain types of reactive silica are present in the aggregates. In consequence, an expansive alkali-silica gel is formed leading to the concrete cracking and degradation. Granites are rocks composed essentially of quartz, micas and feldspars, the latter being the minerals which contain more alkalis in their structure and thus, able to release them in conditions of high alkalinity. Although these aggregates are of slow reaction, some structures where they were applied show evidence of deterioration due to ASR some years or decades after the construction. In the present work, the possible contribution of granitic aggregates to the interstitial fluids of concrete by alkalis release was studied by performing chemical attack with NaOH and KOH solutions. Due to the heterogeneity of the quarries in what concerns the degree of alteration and/or fracturing, rock samples with different alteration were analysed. The alteration degree was characterized both under optical microscope and image analysis and compared with the results obtained from the chemical tests. It was concluded that natural alteration reduces dramatically the releasable alkalis available in the rocks.

  19. Characterization of kaolin and granite waste for formulation of porcelain stoneware tiles

    International Nuclear Information System (INIS)

    Luna da Silveira, G.C.; Acchar, W.; Gomes, U.U.; Silva, B.K.O.; Luna da Silveira, R.V.; Labrincha, J.A.; Costa, M.C.P.

    2016-01-01

    To produce a stoneware tiles is necessary develop a formulation that satisfies their structural characteristics, micro-structural, physical and mechanical properties. Thus, in order to create a formulation for porcelain stoneware tiles that give use to kaolin and granite waste used in the production of ceramic materials were asked the following characterizations: chemical analysis, mineralogical, thermal and particle size. We found that in the kaolin sample it presents a rate of silicon oxide and aluminum oxide similar to those found in the work of other investigators, about 45.23% SiO2 and 37.39% Al 2 O 3 . In the granite waste, the percentage of silicon oxide and aluminum oxide are also similar to those observed in other studies, with about 74.89% SiO2 and 10.54% Al 2 O 3 . Both the percentage of SiO 2 and Al 2 O 3 founded in these two samples satisfy the percentage required in the manufacturing of porcelain stoneware tiles. (author)

  20. Plutonium speciation in selected basalt, granite, shale, and tuff ground waters

    International Nuclear Information System (INIS)

    Cleveland, J.M.; Nash, K.L.; Rees, T.F.

    1983-01-01

    The speciation of added plutonium was determined in ground waters of widely varying composition from four rock types: basalt, granite, shale, and tuff. Plutonium was soluble in the basalt water, which contained a high fluoride ion concentration, probably as a result of its stabilization in solution as fluorocomplexes, primarily of plutonium (IV); it was insoluble, however, in the shale ground water, which contained the highest concentration of sulfate ion. Results were intermediate in the granite and tuff ground waters. In synthetic waters containing significant concentrations of both sulfate and fluoride, the effects were smaller and less predictable. Dissolved oxygen, ionic strength, carbonate ion concentration, and pH had little effect on plutonium speciation in the ranges encountered in this study. However, other ionic species not involved in this study may also influence plutonium speciation. The results have potential significance in establishing site-selection criteria for radioactive waste repositories. All other factors being equal, host rocks whose associated waters contain low concentrations of free fluoride ion should be preferable for the location of waste repositories

  1. Immobilization technologies for the management of hazardous industrial waste using granite waste (case study)

    Energy Technology Data Exchange (ETDEWEB)

    Lasheen, Mohamed R.; Ashmawy, Azza M.; Ibrahim, Hanan S.; Moniem, Shimaa M. Abdel [National Research Centre, Giza (Egypt)

    2016-03-15

    Full characterization of granite waste sludge (GWS) was accomplished by X-ray diffraction (XRD) and Xray fluorescence (XRF) for identification of its phase and chemical composition. Different leaching tests were conducted to determine the efficiency of the GWS for metal stabilization in hazardous sludge. The leaching of the metals from stabilized contaminated sludge was decreased as the GWS amount increased. Only 15% of GWS was sufficient for stabilization of all metal ions under investigation. The main reason for metal immobilization was attributed to the aluminosilicates or silicates matrix within the GWS, which can transform the metals in the form of their insoluble hydroxides or absorbed in the stabilized matrix. Also, solidification/stabilization technique was used for remediation of contaminated sludge. Compressive strength test after curing for 28 days was used for measuring the effectiveness of remediation technique; it was found to be 1.88MPa. This indicated that the remediated sludge was well solidified and safe to be used as a raw substance for roadway blocks. Therefore, this huge amount of by-product sludge derived from the granite cutting industry, which has a negative environmental impact due to its disposal, can be utilized as a binder material for solidification/stabilization of hazardous sludge.

  2. Coupled thermo-mechanical analysis of granite for high-level radioactive waste repository

    International Nuclear Information System (INIS)

    Liu Wengang; Wang Ju; Zhou Hongwei; Jiang Pengfei; Yang Chunhe

    2008-01-01

    High-level radioactive wastes (HLW) repository is a special deep underground engineering, and in the stages of site selection, designing, constructing ,the stability evaluation, lots of important rock mechanics problems need to be resolved. During the decay of nuclear waste, enormous thermal energy was released and temperature variation caused dynamic distribution of stress and deformation field of surrounding rock of repository. BeiShan region of Gansu province was selected to be the repository field in the future, it is of practical significance to do research on granite in this region. Based on the concept model of HLW repository, this thesis calculates temperature field, stress field and deformation field of HLW repository surrounding rock under the condition of TM coupled with applying the finite difference FLAC 3D . From this study, thermo-mechanical characteristic of granite is obtained primarily under given canister heat source and given decay law function. And these results show that the reasonable space between disposal hole is 8 m-12 m, and the peak temperature of the canister surface is 130 ℃, the centerline temperature between pits is about 40 ℃ which is maintained for about hundreds of years under given heating output at -500 m depth. (authors)

  3. RADIOLOGICAL HAZARD INDICES OF GRANITIC ROCKS USED FOR THE CONSTRUCTION OF BUILDINGS FROM NUBA MOUNTAINS SUDAN.

    Science.gov (United States)

    Fadol, Nooreldin; Idriss, Hajo; Salih, Isam; Ragab, Nserdin A; Osman, Safa; Sam, Adam K

    2018-02-12

    This study was conducted to assess the level of radioactivity and the radiation hazards associated with granite rocks used for construction of buildings. The measurement of radioactivity content of the rock samples was performed with gamma-spectrometry equipped with Nal (TI) detector. From the results obtained in this study the average activity concentrations of 226Ra, 232Th and 40K were 20.64, 30.50 and 295.19 Bq kg-1, respectively. The absorbed dose rate in air at 1 m above ground level, the annual effective dose and the gamma index were determined with the aim to assess the possible radiological impact on inhabitants of dwellings built using such rocks. The mean value of the absorbed dose rate, the annual effective dose and the gamma index (Iγ) was 36.36 nGy h-1, 40.79 μSv y-1 and 0.51 μSv y-1, respectively. Radium equivalent activities, and external and internal hazard indices, were also calculated. These data indicated that the area of study lies within areas recognized as normal background radiation and the granite rocks are safe to be used as building material and other structural purposes. © The Author(s) 2018. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. A rapid method of extraction of uranium and thorium from granite for alpha spectrometry

    International Nuclear Information System (INIS)

    Gascoyne, M.; Larocque, J.P.A.

    1984-01-01

    The lithium metaborate fusion technique for analysis of rock samples has been adapted for the alpha spectrometric determination of uranium and thorium isotope abundances in granite. Powdered granite is spiked with a solution of a uranium-thorium isotope tracer, mixed with LiBO 2 in a 1: 3 ratio and fused at 950 o C in a graphite crucible. The mixture is poured into 1 M HNO 3 and stirred until dissolved. Uranium and thorium are simultaneously extracted with 10% tributylphosphate(TBP) in amyl acetate using AI(NO 3 ) 3 as the salting agent, and then back-extracted into 1 M H 2 SO 4 . Uranium is separated from thorium using anion exchange resin and, after further purification, each is plated onto steel discs for alpha counting. Overall chemical yields are adequate at present (generally 20 to 60%). Preliminary tests show the TBP extraction step to be almost quantitative for both elements, in spite of the presence of silicon and high concentrations of aluminium. This procedure is much faster than the usual acid digestion technique, and uranium and thorium discs for counting can be prepared in approximately eight hours, starting from rock powder. (author)

  5. A rapid method of extraction of uranium and thorium from granite for alpha spectrometry

    International Nuclear Information System (INIS)

    Gascoyne, M.; Larocque, J.P.A.

    1984-01-01

    The lithium metaborate fusion technique for analysis of rock samples has been adapted for the alpha spectrometric determination of uranium and thorium isotope abundances in granite. Powdered granite is spiked with a solution of a uranium-thorium isotope tracer, mixed with LiBO 2 in a 1:3 ratio and fused at 950 0 C in a graphite crucible. The mixture is poured into 1 M HNO 3 and stirred until dissolved. Uranium and thorium are simultaneously extracted with 10% tributylphosphate (TBP) in amyl acetate using Al(NO 3 ) 3 as the salting agent, and then back-extracted into 1 M H 2 SO 4 . Uranium is separated from thorium using anion exchange resin and, after further purification, each is plated onto steel discs for alpha counting. Overall chemical yields are adequate at present (generally 20 to 60%). Preliminary tests show the TBP extraction step to be almost quantitative for both elements, in spite of the presence of silicon and high concentrations of aluminium. This procedure is much faster than the usual digestion technique, and uranium and thorium discs for counting can be prepared in approximately eight hours, starting from rock powder. (orig.)

  6. A rapid method of extraction of uranium and thorium from granite for alpha spectrometry

    Science.gov (United States)

    Gascoyne, M.; Larocque, J. P. A.

    1984-06-01

    The lithium metaborate fusion technique for analysis of rock samples has been adapted for the alpha spectrometric determination of uranium and thorium isotope abundances in granite. Powdered granite is spiked with a solution of a uranium-thorium isotope tracer, mixed with LiBO 2 in a 1:3 ratio and fused at 950°C in a graphite crucible. The mixture is poured into 1 M HNO 3 and stirred until dissolved. Uranium and thorium are simultaneously extracted with 10% tributylphosphate (TBP) in amyl acetate using Al(NO 3) 3 as the salting agent, and then back-extracted into 1 M H 2SO 4. Uranium is separated from thorium using anion exchange resin and, after further purification, each is plated onto steel discs for alpha counting. Overall chemical yields are adequate at present (generally 20 to 60%). Preliminary tests show the TBP extraction step to be almost quantitative for both elements, in spite of the presence of silicon and high concentrations of aluminium. This procedure is much faster than the usual acid digestion technique, and uranium and thorium discs for counting can be prepared in approximately eight hours, starting from rock powder.

  7. The geology of uranium in the Saint-Sylvestre granite district (Limousin, Massif Central, France)

    International Nuclear Information System (INIS)

    Marquaire, C.; Moreau, M.; Barbier, J.; Ranchin, G.; Carrat, H.G.; Coppens, R.; Senecal, J.; Koszotolanyi, C.; Dottin, H.

    1969-01-01

    This report concerns the geology of uranium in Limousin, more particularly in the St-Sylvestre massif, and the related phenomena: regional geology, petrographic and geochemical zonal distribution observed in various granite massifs, uranium movement in connection with surface alteration, geochronology of uranium ore. The work is made up of six articles covering the various scientific aspects listed above. Each article is headed with an abstract. The paper comprises the following chapters: Foreword by Marcel ROUBAULT. 1. Ch. MARQUAIRE, M. MOREAU Outline of geological conditions in Northern Limousin and distribution of uraniferous occurrences. 2. J. BARBIER, G. RANCHIN, H. G. CARRAT and R. COPPENS Geology of the St-Sylvestre Massif and uranium geochemistry - Introduction to laboratory studies - Problems of methodology. 3. J. BARBIER and G. RANCHIN Petrographical and geochemical zones in the St-Sylvestre granite massif (Limousin - French 'Massif Central'). 4. J. BARBIER and G. RANCHIN Uranium geochemistry in the St-Sylvestre Massif (Limousin - French 'Massif Central') - Occurrences of primary geochemical uranium and replacement processes. 5. J. SENEGAL Monograph of the Brugeaud orebody. 6. R. COPPENS, Ch. KOSZTOLANYI and H. DOTTIN Geochronological study of the Brugeaud mine. 1969. (authors) [fr

  8. Soil-gas radon monitoring in an active granite quarry from central Portugal

    Science.gov (United States)

    Pereira, A. J. S. C.; Barbosa, S. M.; Neves, L. J. P. F.; Aumento, F.

    2011-07-01

    Seven soil-gas radon monitoring stations were placed along the active front of a granite quarry in Canas de senhorim, Central Portugal, recording continuously for 81 days. Important differences in the radon concentration were found between stations, with average values comprised between 102 and 2982 Bq m-3, which can be explained by the local presence of uranium anomalies in the regional late-orogenic Hercynian granite, usually associated with faults. One of the boreholes exhibits large radon anomalies lasting for several days, and two, contrary to the others, show a clear daily periodic behaviour, with minima around 19:00 LT and maxima around 07:00 LT. The different patterns observed in stations placed at such a short distance (<100 m) has no clear explanation and deserves further investigation. Data analysis shows no evidence of soil-gas radon concentration changes during explosions carried out at the quarry. This is likely to result from the absence of a progressive stress field affecting the rock, as typically occurs before an earthquake.

  9. Soil-gas radon monitoring in an active granite quarry from central Portugal

    Directory of Open Access Journals (Sweden)

    A. J. S. C. Pereira

    2011-07-01

    Full Text Available Seven soil-gas radon monitoring stations were placed along the active front of a granite quarry in Canas de senhorim, Central Portugal, recording continuously for 81 days. Important differences in the radon concentration were found between stations, with average values comprised between 102 and 2982 Bq m−3, which can be explained by the local presence of uranium anomalies in the regional late-orogenic Hercynian granite, usually associated with faults. One of the boreholes exhibits large radon anomalies lasting for several days, and two, contrary to the others, show a clear daily periodic behaviour, with minima around 19:00 LT and maxima around 07:00 LT. The different patterns observed in stations placed at such a short distance (<100 m has no clear explanation and deserves further investigation. Data analysis shows no evidence of soil-gas radon concentration changes during explosions carried out at the quarry. This is likely to result from the absence of a progressive stress field affecting the rock, as typically occurs before an earthquake.

  10. Regional metallogenic essential factor of granite-type uranium deposits in Guangdong province

    International Nuclear Information System (INIS)

    Pan Yongzheng

    1987-12-01

    The uranium origin, activation region, red basin, and fault depressed zone constitute the regional metallogenic essential factor of the four united like one granite-type uranium deposits in the post-Caledonian rise area in China. In the development of sub-geosyncline in the Caledonian, the clastic formation with widely deposited carbon, silicon, mud rich bearing organic matter, which drow a great amount of uranium formed the uranium-bearing system in the Sinian-Cambrian period. The magmagranite activation in a large scale in the Indosinian-Yenshanian period caused the continental crust to be suffered strong reformation and the uranium-bearing basement system to be eroded and remelted, and formed the rich uranium granite body. The multiple structure-magmatic movement further made the uranium in the rock body suffered the endogenic, structure, supergene active reformation, and produced mobile uranium concentrated area. Under the dry and hot paleoclimate condition in the Cretaceous-Tertiary period, strong weathering and hot water leaching forced uranium to be concentrated into the 'rock origin activation' type uranium deposits in the fault depressed zone

  11. Experimental and numerical study of drill bit drop tests on Kuru granite

    Science.gov (United States)

    Fourmeau, Marion; Kane, Alexandre; Hokka, Mikko

    2017-01-01

    This paper presents an experimental and numerical study of Kuru grey granite impacted with a seven-buttons drill bit mounted on an instrumented drop test machine. The force versus displacement curves during the impact, so-called bit-rock interaction (BRI) curves, were obtained using strain gauge measurements for two levels of impact energy. Moreover, the volume of removed rock after each drop test was evaluated by stereo-lithography (three-dimensional surface reconstruction). A modified version of the Holmquist-Johnson-Cook (MHJC) material model was calibrated using Kuru granite test results available from the literature. Numerical simulations of the single drop tests were carried out using the MHJC model available in the LS-DYNA explicit finite-element solver. The influence of the impact energy and additional confining pressure on the BRI curves and the volume of the removed rock is discussed. In addition, the influence of the rock surface shape before impact was evaluated using two different mesh geometries: a flat surface and a hyperbolic surface. The experimental and numerical results are compared and discussed in terms of drilling efficiency through the mechanical specific energy. This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

  12. Study on Dynamic Compressive Mechanical Properties and Failure Modes of Heat-Treated Granite

    Directory of Open Access Journals (Sweden)

    Zhiliang Wang

    Full Text Available Abstract Temperature and external load are two important factors affecting the mechanical properties of rock material. The test on heat- treated granite specimen was carried out by using an improved split Hopkinson pressure bar (SHPB. Based on the test data, the dynamic behavior and failure characteristics of the granite under the coupling action of temperature and impact loading are studied. The results show that the amplitude of incident wave increases with the impact velocity of striker, and the shapes of the transmitted and reflected waves are closely related to the failure state of the specimen. The stress-strain curves for the heat-treated specimens above 700oC are obviously different to those below 500oC in terms of the slopes for the ascending segment and the peak stress, indicating that there is a temperature threshold between 500oC and 700oC. Under the same velocity, the strain rate decreases slightly and then increases as the temperature increases. At a constant temperature, strain rate increases linearly with the impact velocity. The relationship between elastic modulus and strain rate for the heat-treated specimen obviously tends to have no regularity. In addition, both peak stress and peak strain exhibit strain rate sensitivity, but different increasing rates for different temperatures are detected. Below 500oC, the influence of temperature on peak stress and peak strain is not evident, however, the influence becomes remarkable at 700oC and 900oC.

  13. Prediction of the Cut Depth of Granitic Rocks Machined by Abrasive Waterjet (AWJ)

    Science.gov (United States)

    Aydin, Gokhan; Karakurt, Izzet; Aydiner, Kerim

    2013-09-01

    In this paper, an experimental study on the cut depth, which is an important cutting performance indicator in the abrasive waterjet (AWJ) cutting of rock, was presented. Taguchi experimental design of an orthogonal array was employed to conduct the experiments. A variety of nine types of granitic rocks were used in the cutting experiments. The experimental data were used to assess the influence of AWJ operating variables on the cut depth. Using regression analysis, models for prediction of the cut depth from the operating variables and rock properties in AWJ machining of granitic rocks were then developed and verified. The results indicated that the cut depths decreased with increasing traverse speed and decreasing abrasive size. On the other hand, increase of the abrasive mass flow rate and water pressure led to increases in the cut depths. Additionally, it was observed that the standoff distance had no discernible effects on the cut depths. Furthermore, from the statistical analysis, it was found that the predictive models developed for the rock types had potential for practical applications. Verification of the models for using them as a practical guideline revealed a high applicability of the models within the experimental range used.

  14. Emplacement mechanisms and structural influences of a younger granite intrusion into older wall rocks - a principal study with application to the Goetemar and Uthammar granites. Site-descriptive modelling SDM-Site Laxemar

    Energy Technology Data Exchange (ETDEWEB)

    Cruden, Alexander R. (Dept. of Geology, Univ. of Toronto (Canada))

    2008-12-15

    The c. 1.80 Ga old bedrock in the Laxemar-Simpevarp area, which is the focus of the site investigation at Oskarshamn, is dominated by intrusive rocks belonging to the c. 1.86-1.65 Ga Transscandinavian Igneous Belt (TIB). However, the site investigation area is situated in between two c. 1.45 Ga old anorogenic granites, the Goetemar granite in the north and the Uthammar granite in the south. This study evaluates the emplacement mechanism of these intrusions and their structural influence on the older bedrock. Field observations and structural measurements indicate that both the Goetemar and the Uthammar granites are discordant and have not imposed any significant ductile deformation on their wall-rocks. The apparent conformity of geological contacts and fabrics in the wall rocks and the southern margin of the Goetemar granite is coincidental and inherited from the pattern of Svecokarelian deformation of the TIB. However, interpretation of regional aeromagnetic data suggests that the granites occur within a broad, NNE-SSW trending linear belt, pointing to deep seated tectonic control on their generation, ascent and emplacement. Thermochronology indicates that the granites were emplaced at depths between 4 and 8 km into brittle wall rocks. The 3-D shape of the Goetemar and Uthammar plutons has been investigated by 2.75D forward modelling of the residual gravity anomalies due to both granites. Both granites are associated with strong residual gravity anomalies of up to -10 mgal. Constraints on the geometry of the plutons at the surface are provided from surface geology maps and several deep boreholes located on or close to the model profiles. A further variable in the gravity modelling is introduced by either allowing the upper contact of the plutons to assume the most suitable orientation to produce the best fit between the modelled and observed gravity ('unconstrained models') or by forcing the near surface orientation of the contacts to be vertical (&apos

  15. Emplacement mechanisms and structural influences of a younger granite intrusion into older wall rocks - a principal study with application to the Goetemar and Uthammar granites. Site-descriptive modelling SDM-Site Laxemar

    International Nuclear Information System (INIS)

    Cruden, Alexander R.

    2008-12-01

    The c. 1.80 Ga old bedrock in the Laxemar-Simpevarp area, which is the focus of the site investigation at Oskarshamn, is dominated by intrusive rocks belonging to the c. 1.86-1.65 Ga Transscandinavian Igneous Belt (TIB). However, the site investigation area is situated in between two c. 1.45 Ga old anorogenic granites, the Goetemar granite in the north and the Uthammar granite in the south. This study evaluates the emplacement mechanism of these intrusions and their structural influence on the older bedrock. Field observations and structural measurements indicate that both the Goetemar and the Uthammar granites are discordant and have not imposed any significant ductile deformation on their wall-rocks. The apparent conformity of geological contacts and fabrics in the wall rocks and the southern margin of the Goetemar granite is coincidental and inherited from the pattern of Svecokarelian deformation of the TIB. However, interpretation of regional aeromagnetic data suggests that the granites occur within a broad, NNE-SSW trending linear belt, pointing to deep seated tectonic control on their generation, ascent and emplacement. Thermochronology indicates that the granites were emplaced at depths between 4 and 8 km into brittle wall rocks. The 3-D shape of the Goetemar and Uthammar plutons has been investigated by 2.75D forward modelling of the residual gravity anomalies due to both granites. Both granites are associated with strong residual gravity anomalies of up to -10 mgal. Constraints on the geometry of the plutons at the surface are provided from surface geology maps and several deep boreholes located on or close to the model profiles. A further variable in the gravity modelling is introduced by either allowing the upper contact of the plutons to assume the most suitable orientation to produce the best fit between the modelled and observed gravity ('unconstrained models') or by forcing the near surface orientation of the contacts to be vertical ('constrained

  16. The Early Jurassic Bokan Mountain peralkaline granitic complex (southeastern Alaska): geochemistry, petrogenesis and rare-metal mineralization

    Science.gov (United States)

    Dostal, Jaroslav; Kontak, Daniel J.; Karl, Susan M.

    2014-01-01

    The Early Jurassic (ca. 177 Ma) Bokan Mountain granitic complex, located on southern Prince of Wales Island, southernmost Alaska, cross-cuts Paleozoic igneous and metasedimentary rocks of the Alexander terrane of the North American Cordillera and was emplaced during a rifting event. The complex is a circular body (~3 km in diameter) of peralkaline granitic composition that has a core of arfvedsonite granite surrounded by aegirine granite. All the rock-forming minerals typically record a two-stage growth history and aegirine and arfvedsonite were the last major phases to crystalize from the magma. The Bokan granites and related dikes have SiO2 from 72 to 78 wt. %, high iron (FeO (tot) ~3-4.5 wt. %) and alkali (8-10 wt.%) concentrations with high FeO(tot)/(FeO(tot)+MgO) ratios (typically >0.95) and the molar Al2O3/(Na2O+K2O) ratio Nd values which are indicative of a mantle signature. The parent magma is inferred to be derived from an earlier metasomatized lithospheric mantle by low degrees of partial melting and generated the Bokan granitic melt through extensive fractional crystallization. The Bokan complex hosts significant rare-metal (REE, Y, U, Th, Nb) mineralization that is related to the late-stage crystallization history of the complex which involved the overlap of emplacement of felsic dikes, including pegmatite bodies, and generation of orthomagmatic fluids. The abundances of REE, HFSE, U and Th as well as Pb and Nd isotopic values of the pluton and dikes were modified by orthomagmatic hydrothermal fluids highly enriched in the strongly incompatible trace elements, which also escaped along zones of structural weakness to generate rare-metal mineralization. The latter was deposited in two stages: the first relates to the latest stage of magma emplacement and is associated with felsic dikes that intruded along the faults and shear deformations, whereas the second stage involved ingress of hydrothermal fluids that both remobilized and enriched the initial

  17. Zircon U-Pb dating of Archaean granite activity associated with the Jack Hills metasedimentary belt, Yilgarn Craton, Western Australia

    International Nuclear Information System (INIS)

    Pidgeon, R.T.; Wilde, S.A.; Compston, W.

    1990-01-01

    The present study investigates the timing of granitic activity associated with the Jack Hills belt and compares this with the timing of granite activity elsewhere in the Narryer Gneiss Complex in order to constrain models of craton formation. An additional aim was to investigate the granitoids as possible source rocks for detrital zircons found in metasediments within the belt, in particular the 4.2 Ga zircons which form about 12% of the detrital zircon suite from a sample of metaconglomerate. 4 refs., 2 figs

  18. Lithological effects in soil formation and soil slips on weathering-limited slopes underlain by granitic bedrocks in Japan

    OpenAIRE

    Wakatsuki, Tsuyoshi; Matsukura, Yukinori

    2008-01-01

    Soil slips occur every few years due to heavy rains on biotite granite (Gb) and hornblende biotite granite (Ghb) slopes in the Taga Mountains, Ibaraki Prefecture, Japan. The occurrence density of soil slips per unit area is 2.7 times greater in the Gb slopes than that in Ghb slopes. We examined the chemical, mineral, physical, and mechanical properties of two soil profiles on soil-slip scars in these slopes to study the effect of bedrock mineral composition on the density of soil slips. For a...

  19. Geochemical constraints on genesis of Paleoproterozoic A-type granite in the south margin of North China Craton

    Science.gov (United States)

    Xue, Shuo; Xu, Yang; Ling, Ming-Xing; Kang, Qing-Qing; Jiang, Xiao-Yan; Sun, Sai-Jun; Wu, Kai; Zhang, Zhe-Kun; Luo, Ze-Bin; Liu, Yu-Long; Sun, Weidong

    2018-04-01

    Paleoproterozoic A-type granites are widely outcropped in the North China Craton (NCC), particularly in the Trans-North China Orogen. However, their genesis and tectonic significance remain obscure. Here we report systematic studies on geochronology and geochemical characteristics of A-type granite in Huayangchuan, south margin of the NCC. The samples are enriched in total alkali (K2O + Na2O > 8.97 wt%), and depleted in MgO (0.84-0.93 wt%), CaO (1.28-1.90 wt%) and P2O5 (0.18-0.20 wt%), with high FeOT/MgO (5.69-6.67). They are characterized by high Zr + Y + Nb + Ce values (1293-1392 ppm) and 10,000 × Ga/Al ratios (3.14-3.35), which are typical characteristics of A-type granite. The Huayangchuan A-type granite can be further classified as A1-type subgroup based on particular geochemical features, e.g., low Y/Nb (0.87-1.00) and Yb/Ta (0.88-1.10). High precision zircon U-Pb dating of the A-type granite by secondary ion mass spectrometry (SIMS) yields Paleoproterozoic 207Pb/206Pb ages of 1829.5 ± 2.5 Ma. The low zircon ɛHf(t) values (-6.97 to -10.45), along with zircon Hf model age of 2.7-2.9 Ga, indicate that the Huayangchuan A-type granite was derived from partial melting of the ancient continental crust with contribution of enriched mantle components. The low zircon δ18O composition (4.00 to 6.78‰) indicates that the zircons were crystallized from low δ18O magmas, which derived from the crust metasomatized by low δ18O mantle fluids or melts. The E-W trend A1-type granitic plutons in the NCC are generally outcropped in a rift tectonic regime, which is consistent with the development of the mantle plume in the Xiong'er district. The large volume of basaltic magmas, generated by mantle plume head, underplated the lower continental crust and formed the Huayangchuan A-type granite.

  20. The effect of surface finishes on outdoor granite and limestone pavers

    Directory of Open Access Journals (Sweden)

    Martínez-Martínez, J.

    2008-06-01

    Full Text Available Two types of ornamental stones, namely granite (Blanco Rafaela or Zarzalejo Granite and microcrystalline limestone (marble known commercially as Gris Pulpis, treated for different surface finishes, were tested for suitability as paving slabs. The finishes tested in both stones were polishing, hammering, honing and flaming, while acid treatment and abrasion were applied to limestone only and sawn finishes were only studied in granite.The stones were tested for the three physical properties that determine suitability for use as paving slabs; flexural strength under a concentrated load, and abrasion and slip resistance. Laboratory freeze-thaw cycle ageing tests were also conducted and flexural strength subsequently evaluated. Stone water sorption proved to be substantially unaltered by the type of finish employed. Finish barely affected flexural strength, except in the case of limestone flaming, where it was lower. Hammering was found to provide good slip resistance in both stones. The best slip performance for granite, however, was found for flamed specimens. Finish was shown to have no effect on abrasion resistance in either of the stone materials. Polished limestone suffered the least damage in freeze-thaw cycles, whereas freeze-thaw resistance was similar in all the granite specimens, regardless of the finish used.Se han estudiado, para su utilización como baldosas de pavimentos, granito (Blanco Rafaela o Granito de Zarzalejo y caliza microcristalina (mármol comercial Gris Pulpis con diferentes acabados. Estos acabados son: pulido, apomazado, abujardado y flameado en ambas rocas y además acabado al ácido y amolado en la caliza. Se han determinado mediante ensayos estandarizados las tres propiedades físicas de mayor interés para el uso de la piedra natural como baldosa en pavimentos de exteriores: resistencia a la flexión bajo carga concentrada, a la abrasión y al deslizamiento. Se han realizado ensayos de durabilidad por ciclos de hielo

  1. Geology and geochemistry of the Redrock Granite and anorthosite xenoliths (Proterozoic in the northern Burro Mountains, Grant County, New Mexico, USA

    Directory of Open Access Journals (Sweden)

    Virginia T. McLemore

    2002-01-01

    Full Text Available Mineral ages from the A-type granites and anorthosite xenoliths in the Redrock area in the northwestern Burro Mountains in southwestern New Mexico cluster around ~1220–1225 Ma and provide yet another example of bimodal igneous activity during this time period in the southwestern United States. The metaluminous to peraluminous, marginally alkaline to subalkaline Redrock Granite exhibits the textural, mineralogical, and geochemical features of A-type granitethat was emplaced at a relatively high crustal level. Field relationships, whole rock and mineral geochemical and isotopic trends suggest that the four phases of the Redrock Granite are genetically related, with the miarolitic biotite/alkali feldspar granite being the youngest phase. Spatial relationships and geochemical data suggest that the anorthosite xenoliths were coeval with the RedrockGranite, which is consistent with the anorthosite being derived from the upper mantle, possibly due to deep mantle upwellings, and the Redrock Granite from the lower crust. The process involved melting in the upper mantle, emplacement of anorthosite in the crust resulting in partial crustal melting and thinning, and, finally, intrusion of shallow silicic plutons, the Redrock Granite. The Redrock Granite and anorthosite were presumably derived from sources characterized by subtle, long-term LREE depletion, with εNd (at 1220 Ma values on theorder of +1 to +2.

  2. SHRIMP U-Pb zircon dating of Archean core complex formatio and pancratonic strike-slip deformation in the East Pilbara Granite-Greenstone Terrain

    NARCIS (Netherlands)

    Zegers, T.E.; Nelson, D.R.; Wijbrans, J.R.; White, S.H.

    2001-01-01

    Sensitive high-resolution ion microprobe (SHRIMP) U-Pb dating of zircons from granitic rocks in the East Pilbara Granite-Greenstone Terrain has provided time constraints for main tectonic events in the Shaw Granitoid Complex and has shown that deformation was intricately related to granitoid

  3. The Arctic Coastal Erosion Problem

    Energy Technology Data Exchange (ETDEWEB)

    Frederick, Jennifer M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Thomas, Matthew Anthony [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bull, Diana L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jones, Craig A. [Integral Consulting Inc., San Francisco, CA (United States); Roberts, Jesse D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-09-01

    Permafrost-dominated coastlines in the Arctic are rapidly disappearing. Arctic coastal erosion rates in the United States have doubled since the middle of the twentieth century and appear to be accelerating. Positive erosion trends have been observed for highly-variable geomorphic conditions across the entire Arctic, suggesting a major (human-timescale) shift in coastal landscape evolution. Unfortunately, irreversible coastal land loss in this region poses a threat to native, industrial, scientific, and military communities. The Arctic coastline is vast, spanning more than 100,000 km across eight nations, ten percent of which is overseen by the United States. Much of area is inaccessible by all-season roads. People and infrastructure, therefore, are commonly located near the coast. The impact of the Arctic coastal erosion problem is widespread. Homes are being lost. Residents are being dispersed and their villages relocated. Shoreline fuel storage and delivery systems are at greater risk. The U.S. Department of Energy (DOE) and Sandia National Laboratories (SNL) operate research facilities along some of the most rapidly eroding sections of coast in the world. The U.S. Department of Defense (DOD) is struggling to fortify coastal radar sites, operated to ensure national sovereignty in the air, against the erosion problem. Rapid alterations to the Arctic coastline are facilitated by oceanographic and geomorphic perturbations associated with climate change. Sea ice extent is declining, sea level is rising, sea water temperature is increasing, and permafrost state is changing. The polar orientation of the Arctic exacerbates the magnitude and rate of the environmental forcings that facilitate coastal land area loss. The fundamental mechanics of these processes are understood; their non-linear combination poses an extreme hazard. Tools to accurately predict Arctic coastal erosion do not exist. To obtain an accurate predictive model, a coupling of the influences of

  4. Geochemical Signature of Magmatic-Hydrothermal Fluids Exsolved from the Beauvoir Rare-Metal Granite (Massif Central, France: Insights from LA-ICPMS Analysis of Primary Fluid Inclusions

    Directory of Open Access Journals (Sweden)

    Matthieu Harlaux

    2017-01-01

    Full Text Available The Beauvoir granite (Massif Central, France represents an exceptional case in the European Variscan belt of a peraluminous rare-metal granite crosscutting an early W stockwork. The latter was strongly overprinted by rare-metal magmatic-hydrothermal fluids derived from the Beauvoir granite, resulting in a massive topazification of the quartz-ferberite vein system. This work presents a complete study of primary fluid inclusions hosted in quartz and topaz from the Beauvoir granite and the metasomatized stockwork, in order to characterize the geochemical composition of the magmatic fluids exsolved during the crystallization of this evolved rare-metal peraluminous granite. Microthermometric and Raman spectrometry data show that the earliest fluid (L1 is of high temperature (500 to >600°C, high salinity (17–28 wt.% NaCl eq, and Li-rich (Te100 m and interaction with external fluids.

  5. Smolt Monitoring at the Head of Lower Granite Reservoir and Lower Granite Dam; Smolt Monitoring by Federal and Non-Federal Entities, 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Buettner, Edwin W.; Putnam, Scott A.

    2002-08-01

    This project monitored the daily passage of chinook salmon Oncorhynchus tshawytscha, steelhead trout O. mykiss, and sockeye salmon smolts O. nerka during the 2000 spring out-migration at migrant traps on the Snake River and Salmon River. In 2000 the Nez Perce Tribe released significant numbers of hatchery chinook salmon and steelhead trout above Lower Granite Dam that were not marked with a fin clip or coded-wire tag. Generally, these fish were distinguishable from wild fish by the occurrence of fin erosion. Total annual hatchery chinook salmon catch at the Snake River trap was 36% of the 1999 number. The wild chinook catch was 34% of the previous year's catch. Hatchery steelhead trout catch was 121% of 1999 numbers. Wild steelhead trout catch was 139% of 1999 numbers. The Snake River trap collected 689 age-0 chinook salmon. During 2000, the Snake River trap captured 40 hatchery and 92 wild/natural sockeye salmon and 159 hatchery coho salmon O. kisutch. Differences in trap catch between years are due to fluctuations not only in smolt production, but also differences in trap efficiency and duration of trap operation associated with high flows. Trap operations began on March 13 and were terminated for the season due to high flows on June 16. There were no down days due to high flows or debris. Hatchery chinook salmon catch at the Salmon River trap was 96%, and wild chinook salmon catch was 66% of 1999 numbers. The hatchery steelhead trout collection in 2000 was 90% of the 1999 numbers. Wild steelhead trout collection in 2000 was 147% of the previous years catch. Trap operations began on March 13 and were terminated for the season due to high flows on May 22. There were no days where the trap was out of operation due to high flow or debris. Travel time (d) and migration rate (km/d) through Lower Granite Reservoir for passive integrated transponder (PIT) tagged chinook salmon and steelhead trout, marked at the head of the reservoir, were affected by discharge. For

  6. Demarcation of coastal vulnerability line along the Indian coast

    Digital Repository Service at National Institute of Oceanography (India)

    Ajai; Baba, M.; Unnikrishnan, A.S; Rajawat, A.S; Bhattacharya, S; Ratheesh, R.; Kurian, N.P.; Hameed, S; Sundar, D.

    Delineation of vulnerability line for coastal region due to dynamic coastal processes and natural coastal hazards is a complex task due to high regional variability and site specific coastal characteristics. A methodology is developed using...

  7. The Use of Portable X-ray Flourescence, Magnetic Susceptibility and Scanning Electron Microscope to Classify, characterize, and Determine Redox State of Granites

    Science.gov (United States)

    Abbott, J. R.; Fellows, S. A.

    2016-12-01

    Utah contains granitic intrusions associated with various ore deposits that vary spatially, temporally, and chemically. Utah is a great location to study mineralization associated with granites because it encompasses three unique geologic provinces and offers a wide array of emplacement configurations. Past studies in Utah have primarily focused on major elements and there is also a paucity of trace analyses and most studies are only on one discrete location. Trace element analysis can be used for classifying granites and also locating potential mineralized granites. Trace element analysis of granites may also lend insight into magma redox, which is important for ore formation. Trace element and redox analyses are both expensive and time consuming. We wanted to determine redox and trace element distribution using tools that are cost effective and readily available. Portable x-ray fluorescence (pXRF) offers an affordable solution to quickly acquire large counts for key trace elements in granites. These semi-quantitative results may also help determine redox. We present a technique to better determine the redox state of granitic rocks using pXRF and magnetic susceptibility a tool that is underutilized in the field. Additionally, we show that mineral mapping of oxides and sulfur-bearing minerals in thin section by SEM, aids in determining the redox state of granites by looking at Fe and Ti ratios and observing the presence of sulfate or sulfide. By utilizing equipment that is readily available and cost effective we are able to better understand the redox state, and mineralizing potential of various granites. This is important to workers interested in locating ore deposits or understanding the granitic system.

  8. Timing of granitic magmatism in the northern Borborema Province, Brazil: a U Pb study of granitoids from the Alto Pajeú Terrain

    Science.gov (United States)

    Bastos Leite, P. R.; Bertrand, J.-M.; de Lima, E. S.; Leterrier, J.

    2000-11-01

    The Alto Pajeú Terrain (APT) is a SW-NE trending fold belt in the Neoproterozoic Borborema Province (NE Brazil), formed by metasedimentary sequences interlayered with metavolcanosedimentary units, both intruded by granitic rocks of different compositions and ages. The tectonic evolution of the APT involves Mesoproterozoic and Neoproterozoic transtensional and contractional tectonic events. In this study, we present U-Pb zircon ages of five granitoids selected according to a generally accepted relative chronology: (a) the Tuparetama granite and Tuparetama migmatitic granite with low angle gneissic foliation represent syn-tangential rocks presumably related to a Transamazonian event; (b) the Amparo granite with high angle gneissic foliation related to the Brazilian/Pan-African event; and (c) the Tabira and Jabitacá post-strike-slip granites. The results obtained do not confirm the generally accepted chronology of events. Granites previously classified in different groups (Tuparetama, Amparo, and Jabitacá) belong to the same orogenic cycle (Brazilian). Large batholiths, previously suspected to have been emplaced after the strike-slip deformation, represent older crustal remnants within them. In each case they consist of particular rock types — an alkaline high-temperature granite (Tabira) and a 'granulite' (Tuparetama migmatitic granite). These older ages imply that pre-Brazilian crust-forming events such as the Transamazonian Orogeny (Tuparetama migmatitic granite estimated at ca. 2050 Ma) and Cariris Velhos event (Tabira granite at ca. 972 Ma) occurred in the APT, and their records survived the intense recycling which characterizes the Brazilian/Pan-African orogeny.

  9. The dynamics of coastal models

    Science.gov (United States)

    Hearn, Clifford J.

    2008-01-01

    Coastal basins are defined as estuaries, lagoons, and embayments. This book deals with the science of coastal basins using simple models, many of which are presented in either analytical form or Microsoft Excel or MATLAB. The book introduces simple hydrodynamics and its applications, from the use of simple box and one-dimensional models to flow over coral reefs. The book also emphasizes models as a scientific tool in our understanding of coasts, and introduces the value of the most modern flexible mesh combined wave-current models. Examples from shallow basins around the world illustrate the wonders of the scientific method and the power of simple dynamics. This book is ideal for use as an advanced textbook for graduate students and as an introduction to the topic for researchers, especially those from other fields of science needing a basic understanding of the basic ideas of the dynamics of coastal basins.

  10. U.S. Coastal Relief Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC's U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone integrating offshore bathymetry with land topography into a...

  11. U.S. Coastal Relief Model - Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC's U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone integrating offshore bathymetry with land topography into a...

  12. Introduction to Coastal Engineering and Breakwaters

    NARCIS (Netherlands)

    Bijker, E.W.

    1972-01-01

    Collegedictaat f11a and f11b. Lecture notes, short waves, waves near shoreline, coastal formation, sediment transport by waves, coastal protection, delta coasts, muddy coasts, tidal rivers, density currents, breakwater design.

  13. Coastal Analysis Submission for Plymouth County, MA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Coastal study data as defined in FEMA Guidelines and Specifications, Appendix D: Guidance for Coastal Flooding Analyses and Mapping (April 2003) and Atlantic Ocean...

  14. Coastal Analysis Submission for Pierce County, WA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Coastal study data as defined in FEMA Guidelines and Specifications, Appendix D: Final Draft Guidelines for Coastal Flood Hazard Analysis and Mapping for the Pacific...

  15. COASTAL STUDY, KITSAP COUNTY,WASHINGTON USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Coastal analysis data as defined in FEMA Guidelines and Specifications, Appendix D: Guidance for Coastal Flooding Analyses and Mapping, submitted as a result of a...

  16. Impact of aquaculture on coastal marine environment

    Digital Repository Service at National Institute of Oceanography (India)

    Ansari, Z.A.; Abidi, S.A.H.

    Since aquaculture is intimately linked with aquatic environmental quality, entry of pollutants to coastal waters constitutes the greatest threat to marine environmental quality and, hence, to long term viability of coastal aquaculture. Fish...

  17. Types and Functions of Coastal Structures

    DEFF Research Database (Denmark)

    Burcharth, H. F.; A. Hughes, Steven

    2003-01-01

    Coastal structures are used in coastal defence schemes with the objective of preventing shoreline erosion and flooding of the hinterland. Other objectives include sheltering of harbour basins and harbour entrances against waves, stabilization of navigation channels at inlets, and protection...

  18. COASTAL Analysis Submission for Middlesex County, CT

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Coastal study data as defined in FEMA Guidelines and Specifications, Appendix D: Guidance for Coastal Flooding Analyses and Mapping (April 2003) and Atlantic Ocean...

  19. Genetic Affiliation of Gold and Uranium Mineralization in El-Missikat Granite, Central Eastern Desert, Egypt

    International Nuclear Information System (INIS)

    Ammar, F.A.; Omar, S.A.M.; El Sawey, El.H.

    2016-01-01

    Gabal El-Missikat granitic pluton is affected by two fault systems trending NW-SE (the oldest) and ENE-WSW directions. It is one of the uranium occurrences in the Eastern Desert of Egypt. The northwestern margins of El-Missikat pluton, along its contact with the gneissose quartz diorite, are dissected by numerous reactivated fractured shear zones running generally ENE-WSW to NE-SW and dipping about 60°-70° to SE. Many white (oldest), smoky or black and jasperoid (youngest) silica veinlets fill the fractures of these shear zones. These veins are of irregular shape and variable thickness ranging from few centimeters to about three meters. They are chiefly affected by silicification, sericitization, hematitization , kaolinization and hydrothermal alterations processes. The smoky black veins are hosting secondary uranium and fluorite-, sulphide-gold mineralizations. Polished surface studies, ICP-ES and Atomic Absorption as well as Scanning Electron Microscope measurements recorded galena, pyrite chalcopyrite, sphalerite and molybdenite in the black and jasperoid mineralized veins. Gold associated with ore mineral assemblage as pyrite, chalcopyrite, sphalerite, galena, sheelite and iron oxides. The identified sulphide minerals not bearing gold are recorded. Gold are relatively coarse-grained, massive and metallic yellow or stretched bronze colored particles. The recorded secondary U minerals associates the sulphide gold-mineralization in the black and jasperoid silica veins. Regarding the mobility of both uranium and gold, U 4+ mobilized in oxidizing medium and migrate and transport as U 6+ , then deposited later as U 4+ when the medium changes to be reducing characterized by high /O 2 . On contrary, gold mobilized when the medium is complex AuCl 3- ion bearing. Consequently, El- Missikat granitic pluton affected by oxidizing Au and Cl 3- bearing high temperature hydrothermal solutions that leached U 4+ , W and Mo from the granitic mass as U 6 + , later decrease of

  20. Comparative study of the alkali-silica reaction (ASR in granitic aggregates

    Directory of Open Access Journals (Sweden)

    Velasco-Torres, A.

    2010-06-01

    Full Text Available The reaction between certain reactive components of aggregates (like opal and metaestable silica and concrete pore solution is well documented. Nevertheless, in this study it has been shown that some aggregates, like granite, could develop a rapid or slow alkali-silica reaction (ASR depending on the deleterious component involved. Mortar bars were cast with two granitic aggregates extracted from concrete cores drilled in two Spanish Dams affected by ASR, being classified as granitic rocks. The main difference between them is the reactive component: microcrystalline quartz in one case and strained and microcracked quartz in the other case. A petrographic examination was carried out in the mortar bars. Thin sections were cut and the alkalisilica gel was stained for an easier detection. Then, the thin sections were examinated with a stereomicroscope comparing the differences in the progress of the ASR for both aggregates. It can be concluded that the main mechanism of formation and storage of gel is associated to the micro-cracks instead of the subgrain boundaries.

    La reacción entre los componentes de la fase intersticial del hormigón y áridos con minerales como el ópalo o la sílice metaestable, se encuentra bien documentada. Sin embargo, en este estudio, se ha detectado que dentro de un mismo tipo de roca, como es el granito, puede haber diferencias en el tipo de reacción (lenta o rápida dependiendo del componente reactivo que aparezca en la misma. Se han fabricado barras de mortero con los áridos extraídos de dos presas españolas afectadas por la reacción álcali-sílice. Estos áridos son rocas graníticas y la diferencia entre ambos reside en que una de las muestras contiene cuarzo microcristalino como componente reactivo y, la otra, cuarzo deformado. Mediante el estudio petrográfico de barras de mortero y el teñido del gel álcali-sílice se ha podido observar la evolución y progreso de la reacción para cada